Name: Mercure Saint-Omer Centre Gare
Address: Saint-Omer
Telephone: (929) 284-2269
Price range: Price starts at 100.99 USD. We adjust our prices regularly
Rating: 4

Le Touquet-Paris-Plage

Boulogne-sur-Mer

Lens

Saint-Nicolas

Saint-Laurent-Blangy

Paris

Rennes

Nantes

Lyon

Bordeaux

Toulouse

Nice

Strasbourg

Marseille

Lille

Châtellerie de Schoebeque

Campanile Béthune

ibis Styles Lens Centre Gare

ibis Styles Béthune Bruay

ibis Styles Bethune Bruay

ibis Saint-Omer Centre

Hôtel Louvre-Lens - Esprit de France

Mercure Saint-Omer Centre Gare

Aire-sur-la-Lys

Home

France

Hauts-de-France

Pas-de-Calais

Exclusive retreats offering the ultimate in comfort and style.

4 & 5-Star Retreat

{count} bookings to come

{count, plural, =0 {​# favorite hotel} one {​# favorite hotel} other {​# favorite hotels}}

Your room will be available from {checkinTime} to {checkoutTime}. If you can let the hotel know when you will be arriving, that will help them to offer you the best possible welcome.

Your arrival time

We have just sent you by email your reservation confirmation.

A new confirmation will be sent to this address

Your request

Find your current Dayuse bookings
and booking history here

No current bookings

My reservations - {shortDomain}

History

Login or register to sync your saved establishments to the device of your choice

Consult your saved establishments wherever you are

My favorite hotels - {shortDomain}

My favorite hotels

Once deleted, your reservation will no longer be visible in your reservation history.

Delete this reservation?

Current bookings

Find your current Dayuse bookings and booking history here

Dayuse does not share any of your information with hotels or third party services.

How is my information managed?

Provide personal information and change your password

My information

Already have an account?

Immerse yourself in one-of-a-kind stays, from boutique gems to architectural wonders.

Beyond the Ordinary

Unbeatable prices for an unforgettable getaway.

Exclusive Hotel Deals You Can’t Miss!

Dive into the best pools, designed for relaxation and luxury.

Our best pools

The highest-rated stays by our guests.

All the Stars

Rooms with breathtaking views that will leave you in awe.

Ultimate Big Apple Views

Your cancellation will be final and the hotel will be notified

Booking

I have reloaded my card

Your request has been registered. The hotel has been informed and will debit the card you've shared

You can no longer recharge  your account or update your payment method

This link has expired

Thanks for the update

Add a card

The page you are looking for is not available, 
but we’re sure to have a room for you

{type} - Page {page} - {shortDomain}

Choose your destination

Select your day

Our Daydream experiences are all-in-one packages we’ve negotiated specially for you. Enjoy a room with exclusive access to wellness areas, restaurants or bars in the most beautiful hotels around {city}, always during the daytime.

Daydream experience

Beautiful hotels, privacy guaranteed. Book a Dayuse hotel for a few hours during the day and save up to 75% compared to the overnight. No credit card required and free cancellation.

Хотелиер сте? Станете част от преживяването Dayuse и се присъединете към партньорската ни хотелска мрежа

Присъединете се към мрежата на Dayuse

Държави

Booked without an account? Enter your reservation number to view, modify or cancel it!

1 Dayuse, 1000 possibilities

Top {country}

Discover how Dayuse.com works: a simple, intuitive guide to booking a hotel room for the day. Enjoy reduced rates, flexible booking, and access to high-end services from partner hotels. Transform your day with Dayuse.com.

Update your information.

Choose your preferences

Support

Important notice

Choose a new password | {shortDomain}

Enter a new password and access your account

Change password

Please allow the APP  to add bookings to your calendar.

Authorise access to the calendar

Authorise access to your position in your settings

Gift card or promotional code

Read authentic reviews of Dayuse.com and discover the experiences of our users. Benefit from their testimonials to understand the advantages of booking a daytime hotel. Join our community and transform your days with Dayuse.com.

Share the Dayuse experience with a loved one, your +1 or even your colleagues by personalizing your message!

Subscribe to our newsletter or follow us on Instagram! We vow to make you dream big and inspire your future adventures.

Stay in contact

An upcoming romantic escape? A special occasion that needs to be celebrated? A desire to explore your city? Dayuse selects establishments from 3 to 5 stars to create the most beautiful experiences.

Romantic

A new office for the day to work in peace and quiet, the perfect place for interviews and staying productive!

Business 

Hold your next meeting in a new location. Brainstorm with your teams in inspiring hotels!

Meeting

Playing tourist for the day is possible. Discover the 5* pools around you. Take a moment to disconnect.

Pool

Jacuzzi, sauna, hammam, fitness room...These hotel amenities are waiting for you...

Wellness

Need a new setting to create content? Our customer service team will be happy to help you find the perfect hotel room.

Photo shoot

A layover during two flights? You can now wait comfortably in a daytime hotel close to your airport.

Layover

Order room service and fill up with delicious food from the hotel!

Enjoy room service

Baby showers, power naps, wedding anniversaries... With Dayuse, upgrade your everyday life!

And...

Secret pools, hidden rooftops, bathtubs with a view... Experience everything your heart desires!

Three good reasons to book with Dayuse

Begin your Dayuse journey by finding the hotel of your dreams. We will explain everything to you!


Search

Choose your room, your time slot and your add-ons

Book

Validate

Booking a hotel room during the day for a few hours opens the door to an infinite number of possibilities.

Enjoy a few hours alone, as a couple, or with friends in a hotel room during the day or evening. Simply select a time slot between 6 a.m. and 11 p.m.

Everything you need to know about Dayuse!

What is a Dayuse experience?

An experience tailored to your preferences

Contact Dayuse

You will not be charged

After this period, the reservation will be non-cancellable and non-refundable.

Thank you!

Enjoy your day at the hotel!

Your message has been sent to {name}

You have been disconnected. Please reconnect again

On three occasions, you have been marked as a no-show by the hotel - meaning that you had not cancelled beforehand.

In order to make a new booking, please contact our Customer Success team by <a href="%link%">clicking here</a>.

In order to make a new booking, please contact our Customer Success team.

Indulge in the finest dining experiences paired with exceptional wines.

Our Wine and Dine Favorites 

Access all your favourites in one click and enjoy our best offers

Added to your favourites

Access to your reservation on your account.  

Or login to your account to access your reservation

Cancel or amend your booking date in a few clicks

Access your reservation

Page not found

You will receive a confirmation e-mail at

Your order is confirmed!

Book with peace of mind

Payment

Personalised message

Add a personalised message

Your e-card

Payment is made in the currency of the country you have selected.

Gift card available only in the selected country

Your lucky recipient

Recipient's e-mail address

From...

Gift a wonderful day to someone who deserves it!

Personalise your Dayuse e-card

Book a room for a few hours, enjoy hotel amenities, and experience timeless relaxation.

Elevate Your Travel Experience

Early arrival, long layover or just in need of rest? Book a room for a few hours at a hotel near the airport or in the city.

Next stop: {city}
Book Your Daytime Haven.

The Dayuse magazine

The best of the best from our 7500 references around the world

Създайте си спомени и се насладете на чисто ново преживяване

Насладете се на качествено време заедно

Свободата да работите в тихата атмосфера на луксозен хотел

Вдигнете нивото на срещите си

Treat yourself to room service

Дайте си почивка от ежедневието

Отделете време за себе си

Насладете се на някои от най-красивите хотелски басейни

Потопете се в басейна

Безкрайните възможности, които може да Ви предоставят дневните хотели

This holiday season, gift a dream day with Dayuse Gift Cards.

Наемете хотел за през деня в три стъпки

До последната минута

Безплатно анулиране

Резервация без предплащане

Плащане в хотела

В сравнение с нощувка

До 75% отстъпка

за дневни хотели

Световен лидер

Generally we've enjoyed our stay in your hotel..and we highly recommend this to others 😃staff are friendly 😊 thank you

Very recommended this place.. I WILL BACK AGAIN

Excellent experience, super friendly and helpful reception staff . Clean , tidy and large room .Highly recommended.

excellent !!! and the staff are so kind and approcheable well 🥰🥰🥰
everything is good and fine!! 

Well customer service, tidy room and nice view.

Great place for a day use! Truly relaxed and a very nice room. 
Value for money!

Fantastic experience. Late check out offered immediately. Fantastic staff. Good value. Wouldn't hesitate to recommend/stay again.

I loved the jacuzzi. That was the best part!

Резервирайте Dayuse хотел за няколко часа през деня и спестете до 75% от цената за нощувка. Не е необходима кредитна карта и анулирането е безплатно.

Dayuse: хотели за през деня от -75%

Discover our daytime hotels just steps from the airport — perfect for a shower between flights or a nap after a red-eye!

Our hotels between flights

Upgrade your romance with an all-day date at the hotel.

Create a day to remember

New all-inclusive experiences

Открийте ексклузивните ни оферти преди всички, като се абонирате за бюлетина ни

Възползвайте се от ексклузивни оферти

The dayDreamer Club

Give in to temptation

Pool hotels

НАД МИЛИОН ИЗТЕГЛЯНИЯ

Приложение, което се грижи за нуждите Ви!

Доверяват ни се:

People who have tried daytime hotels have not been disappointed. Read about their experiences!

1 million satisfied customers
in over 29 countries

Резервирайте стая за няколко часа и се насладете на удобствата

Присъединете се към общността ни, за да се вдъхновите

Offer tailored for you

How would you rate the fluidity and efficiency of the check-in process at the hotel?

How would you rate the equipment and amenities in the hotel and your room?

How was your stay at {name}

Would you recommend Dayuse to a friend or colleague?

Your experience with Dayuse

How would you rate the cleanliness of the hotel and your room?

How would you rate the quality of service and the friendliness of the hotel staff?

Your feedback is key to helping us provide you with the best experience!

How would you rate the perceived value for money of your Dayuse experience?

{hotelName} offers these options to enhance your experience

Address

Best Dayuse Hotels List in {country} - Hotels by the hour  | {shortDomain}

Our nearby hotels

Standard booking

Please note that the taxes and fees below will be added to your booked offer:

Taxes and fees

Best Dayuse Hotels List - Hotels by the hour | {shortDomain}

Description

About the hotel

Amenities

Как работи?

Frequently asked questions

How to get there

Location

In the room

Available time slots

Taxes and Fees

Want a little something extra?

Choose your payment method

Gallery

This hotel applies slight price variations on certain dates. Generally on weekends and during school holidays.

Price changes on this date

Reviews

Information

Specific Conditions

Inspiring place

Upmost friendliness

Dreamy bathroom

Delightful breakfast

Safe haven

Explore Neighborhood

Cristal clear waters

Foodies' HQ

Comfy room

Caring staff

Workout addict

Perfect location

Breathtaking view

Royal well-being

Always connected 

Upgrade meeting 

Must-see

Convenient parking

We're liking this

Dayuse Hotels • Hotels by the hour | {shortDomain}

Book a hotel room during the daytime and enjoy all of the hotel’s facilities for less

Enjoy a hotel during the day in {city}

Book a hotel room during the daytime and enjoy all of the hotel’s facilities for less than the night rate

Work from a hotel during the day in {city}

Topics about Dayuse

Discover all our hotels in {city}

Need more inspiration? 

Welcome back !

Dayuse gift card purchases cannot be cancelled or refunded.

Can a gift card be cancelled and refunded?

You are solely responsible in the event of the loss, theft, destruction or unauthorised use of your gift card.

What should I do if I lose my gift card?

If the balance on the gift card does not cover the entire reservation, you will need to make an additional payment online.

What happens if the cost of my reservation is greater than the value of my gift card?

Once you’ve used your gift card, you will then be sent a new gift card for the remaining balance.

What if the cost of my reservation is less than the value of my gift card?

A Dayuse gift card allows you to give a loved one a memorable daytime experience, either by themselves or with a companion, at an upmarket hotel.

What is a Dayuse gift card?

Dayuse Gift Cards are only available to purchase on our website, at the following link. 
After making your purchase, you will receive a gift card code that will also be sent to you by e-mail.

How can I purchase a gift card?

You can only use your gift card on the Dayuse website and only in the United Kingdom. It is not possible to pay using a Dayuse gift card at the hotel. 
Taxes and other charges will have to be paid at the hotel and cannot be paid by gift card.

How do I use my gift card?

We currently accept all major credit cards for purchases of digital gift cards at Dayuse.com

What payment methods does Dayuse accept?

If you cancel a reservation made using a gift card, you will receive a new gift card for the cost of the reservation.

Can I cancel a reservation that’s been paid for using a gift card?

All gift cards purchased on Dayuse.com come in digital format only.

Are the gift cards physical or digital?

Discover the Dayuse gift card: not just a gift, a memorable experience at a luxury hotel. Choose the value and simply enjoy!

Daytime hotel gift card | E-card {domain}

You’re sure to conjure a smile!

Give a little magic with the Dayuse e-card

With plenty of partner hotels worldwide, you’re guaranteed to find what you're looking for.

Luxurious hotels all over {country}

Choose the value and design to make the right impression.

Customisable card

The perfect gift to get away from it all for a day.

Day trip

A memorable experience for one or two people.

Alone or with a companion

Customising

Giving

How the gift card works

Dayuse allows you to enjoy an unforgettable experience with access to a room for the day plus all the hotel’s facilities: spa, room service, swimming pool, bar, etc.

Enjoy a magical day

Follow Dayuse's recommendations

Experience a day getaway in dream hotels at affordable prices

Open the door to exceptional hotels with luxurious facilities and amenities.

Escape for a day full of surprises. Disconnect just a few steps from home.

Benefit from discounts of up to 75% off the nightly rate. Affordable luxury.

Dream Hotels

At affordable prices

Our selection of hotels for Valentine's Day

Hotels for Valentine's Day 2023 • Book a romantic hotel for a day! | {domaine}

Discover our special Valentine's Day offers

Experience an enchanting getaway in a romantic hotel for Valentine's Day. A perfect moment to share.

Dive into luxury with our selection of hotels with elegant pools for an unforgettable day of relaxation.

Treat yourself to a day of absolute wellness in a hotel with a steam room and spa. Put on a bathrobe and bubble away the day.

Celebrate love with an optional bottle of champagne. Ideal to make this day even more magical.

Enjoy our limitless gastronomic offers while spending time with your loved one. Spend the day exploring the world of amazing food!

A timeless day for two

A moment of love and fresh water

Steamroom & spa, the wellness selection

Champagne? With pleasure!

Delectable cuisine? Of course!

Getaway for two

Royal Pool

Bubble of serenity

Extra Champagne

Extra Yummy

Surprise your other half with our Valentine's Day offers

Experience a magical day for Valentine's Day

A Dayuse experience for two is about sharing an unforgettable moment, experiencing emotions and creating memories that will last a lifetime.

Create memories this Valentine's Day

Trending stays in {city}

We'll be back soon

WE'RE DOWN FOR MAINTENANCE

Explore hotels in {city}

{seoTitle} : Book a hotel room for a few hours with {shortDomain} from {priceFrom}. Book without a credit card and cancel free of charge.

{seoTitle} : Book a hotel room for a few hours with {shortDomain}. Book without a credit card and cancel free of charge.

Réservez votre chambre d'hôtel en journée à {seoTitle} ✓ Prix réduit ✓ Annulation gratuite ✓ Réservation sans carte bancaire

Hourly Hotels and Day hotels Available in {city}

{hotelName}, {city} : -{discount}% during the day - {shortDomain}

{hotelName}, {city} : hotel during the day - {shortDomain}

Hourly Hotels in {seoTitle} • Day Hotels | Dayuse

Handpicked hotels in city centers or near airports—perfect for your next stopover.

Travelers' Top Picks

E-mails inspired by destinations that interest you and newsletters containing offers.

Newsletter

To download HD images, our logo or pictures of our hotel partners, click here

What the international press says about us

Are you interested in learning more about the Dayuse Story or testing our service?

Dayuse in the spotlight!

Fast facts

Dayuse opens the doors to hotels during the day enabling a new clientele to live life to the fullest. Upgrade your daily routine, share special occasions, or live in the moment: there are as many possibilities as there are hotels close to you to discover for a few hours!

Transforming hotels into living spaces is Dayuse’s mission. We are committed to making this new lifestyle trend, that is here to stay, increasingly accessible. The global platform for booking daytime hotel experiences has generated nearly half a billion dollars in business volume for its 7,500 hotel partners in 26 countries since its inception.

Newsroom

Whether alone or with a companion, enjoy a hotel room during the day or evening for a few hours. Simply choose your time slot between 6am and 11pm.

Sample the daytime hotel experience!

Select a date

Find your dream hotel

Use the filters to find the experience you’re looking for

Book the time slot and make your selection

How does it work?

Free cancellation

Pay at the hotel

Up to 75% off

World leader

Freedom.  
Flexibility. 
Peace of mind.

Enable location services to quickly locate hotels near you

Enable location services

Benefit from our exclusive promotional offers

Discover new hotels first

Receive our tips to ensure the best experience

Enable push notifications

Between 30% & 75% off  the night rate

Free cancellation, payment at the hotel & no credit card required

Customer service available 7 days a week for you and your customers

4.8/5 on TrustPilot with over 20,000 reviews

An unparalleled customer experience

Just fill out the form below and our dedicated Sales team will contact you shortly. 

Start working with Dayuse

Our financial investor

Attract travelers with early departures, late arrivals or long stopovers.

Maximize your amenities by catering to new high-spending guests.

Optimize your empty rooms by answering consumers' needs for a private and secured space.

Boost your revenue with guests in search of a luxury daycation.

Profit from digital nomads seeking a productive environment.

Incremental revenue for all types of hotels

Our Financial Investor

Present in 29 countries with over 9,000 partners, Dayuse is the world leader in daytime hotel reservations. Dayuse is keeping pace with changing consumer trends by inventing a new way to experience hotels.

The world's leading provider of daytime hotel reservations.

"The role of the hotel has changed. For more than 10 years, we have supported our partners in this evolution through the diversification of their sources of income. Our role is to boost their turnover and increase their occupancy by attracting new customers."

Pioneer for over 10 years

by selling your empty rooms during the day

Increase your turnover

Attract new local customers

Optimize your occupancy rate

Bring your hotel to life during the day

Easily implement the Dayuse solution in your current organization.

The longer the time slot is, the more demand you will drive.
5-hour minimum:
early break Optional, 
classic 11am to 5pm, 
late break optional

Display your standard category and widen the choice with premium categories.

Adjusted to your capacity & operations, no daily management needed. Flexible model with portal access to increase or decrease allocations.

Flat rates that build loyalty have a positive impact on your sales volume. In line with the comp set.

Boost amenity sales and increase your bottom line (spa access, food & beverages, parking...)

An easy-to-implement solution

The French lower mid-cap investment specialist

Boost your revenue by attracting a new daytime clientele

Offer a innovative service to local customers who are looking for new experiences.

Provide a new space for a few hours to mobile workers or business travellers.

Allow travellers to relax and unwind during their stopovers

Leisure

Business

Transit

A new, local, and premium clientele

Our latest articles

Need more information? Download our FREE guide now!

Reminder - You can cancel free of charge!

Click on "cancel your reservation", it's as simple as that!

From your booking confirmation email.

Manage your upcoming reservations in one simple click.

From your Dayuse account.

For increased privacy, manage your bookings by calling us directly!

By phone, with our customer support team.

In order to ensure that our hotel partners are able to welcome you in the best conditions, please see below our advice to best manage your bookings free of charge and in a few clicks.

{name}, manage your future bookings in only a few steps.

For future bookings, we can request credit card information if a cancellation is not declared.

Dear Client,

Thank you for your feedback regarding booking N°{ref}. We have contacted the hotel to ensure this error does not reoccur.

Please disregard the credit card payment alert and rest assured that you will not be penalised.

We look forward to your next Dayuse!

Regarding booking n°{ref}

Check out genuine Dayuse reviews and discover why our service is so popular! Enjoy an extraordinary Dayuse experience and join thousands of satisfied guests who’ve transformed their days with our exclusive offers.

Find a daytime hotel

Only your first name will be published with your comment.
You can modify this field or leave it empty

Your feedback is much appreciated and invaluable in improving 
our services so that we can find the best hotels (and offers) for you!

Thanks {pseudoName} for your feedback !

Rate your hotel

Leave a review

The dayuse rewiews provide you with useful information concerning different clients experiences with Dayuse. These reviews are certified by our external partner Trustpilot and they verify the truthfulness of the information and the reviews that a posted on our website

Dayuse reviews: Find all the certified reviews from our clients.

These reviews allow you to get an insight on the best experiences clients have had with Dayuse, the reviews on Dayuse are very important because they allow us to adapt and better our new offers based on your wants and desires 

Improving the experience thanks to the reviews.

Routine is not really our style, with Dayuse discover the hotel life during the day and rediscover your city. We believe that local tourism allows you to enjoy experiences closer to home.

Rediscover your city with Dayuse.

With your reviews and experiences on our website we can improce the service and always provide more out of the ordinary hotels and experiences. For example, on Dayuse you can add little extras to make your adventure an unforgettable one. So what will you choose a bottle of champagne or the box of games?

How to improve the Dayuse service? 

Book a getaway you will never forget in a hotel that's only a stone's throw away from home. 20,000 users have already left their reviews on Trustpilot. Will you be the next one?

International reviews and services.

Book a getaway you will never forget in a hotel that's only a stone's throw away from home. Over 2500 users have already left their reviews on Trustpilot. Will you be the next one?

Perfect places to celebrate love and life's milestones.

Carrie Bradshaw & Mr.Big Moment

Enjoy luxury and comfort with a soothing bath in your room.

Private baths

Relax in luxurious king-size beds designed for maximum comfort and rejuvenation.

Dream Bigger, Sleep Better

Our top 15 hotels with glowing staff reviews.

Hospitality at Its Best

Our best experiences in {city}

Our best *all-inclusive* experiences selected for you

Try the Daydream filter

Turn off the Daydream filter to see all available hotels

All filters

Try adjusting your search

No hotel available

*Only on selected hotels with online payment

Save 10% on your first booking

Our top hotels for a perfect stopover

No experiences available on the selected date

Live a daytime experience at a hotel

Freshen up between flights

Get some shut eye in a King size bed

Relax by the pool

Step into your ideal workspace

Enjoy a hotel room during the day

Turn transit time into prime time with AM or PM sanctuaries

Your room, anytime in the day

Discover our hotels around international airports

Our offers in 29 countries

Whether you're arriving early, between flights, or seeking a midday retreat. These services enhance your daytime stay with all the comforts you deserve.

Top-tier amenities for a seamless daytime stay

Explore our handlepicked city-center hotels,
perfectly placed for easy access to everything

Haven't found what you're looking for yet?
Access all our hotels with a simple search

Add a message

Contact informations

Your ride is sorted: book stays with shuttle services (free or paid).

Hassle-Free Connections

Google or direct search

Our hotel partners

Other

Press

Social Media

Street advertising

Word-of-mouth

Other (Please specify)

Privacy or Discretion

Transit 

Work

We're sorry we didn't live up to your expectations.\r\nTell us more so we can improve your next experience!

Describe the problem you encountered, to help us improve our service.

What happened?

We hope your booking experience met all your expectations.\r\nTell us all about it by clicking below!

How did it go?

Your extra

Time of arrival

Booking - {shortDomain}

Help us better meet your needs! Take a moment to share your experience with one of our experts—your feedback makes all the difference.

When a booking is not honored without prior cancellation, it impacts the hotel, which has prepared the room especially for you.

Remember to cancel if you are unable to attend! It is possible until the last minute on the site if you have created an account or via your confirmation email

<styled>The hotel is informed of your arrival.</styled>
We have just sent you a booking confirmation to {email}.

Your daytime reservation is confirmed!

Your daytime reservation is <styled>pending confirmation</styled>

Your message has been successfuly sent to {Firstname}.

Dayuse offers the unique flexibility of last-minute cancellations.

No-shows hurt our hotel partners and risk this benefit. Cancel if you can’t make it - together, we’ll keep this option available!

Let’s Protect This Unique Flexibility!

Special requests to be sent to the hotel

Commitment to Your Reservation

No-shows affect our hotel partners and reduce availability for other travelers.

If your plans change, please cancel or modify your booking in advance.

Repeated no-shows may result in requiring a payment method on file and charging a fee for any future no-shows.

FRIENDLY REMINDER

Reservation Beneficiary

Identification

You cannot proceed your booking

The hotel has {nbHours} hours to guarantee availability. 
Otherwise, your request will be automatically cancelled.

Personalization

Close details

See my booking

Special requests

Contact hotel

Free cancellation (excluding booking fee)

Payment ({formattedPrice}) is made in the currency of the hotel

Any additional taxes must be paid directly to the hotel. For your information:

Prepayment of {formattedPrice} to be paid online. The reservation amount will be paid when you check-in at the hotel.

Hourly Hotels and Day hotels Available in Aire-sur-la-Lys