Leave the busy world behind and unwind
A day just for you, under half an hour from Rotterdam and Dordrecht. Twelve saunas, warm and cold baths, treatments and a calm restaurant, set in the polder of 's-Gravendeel.
On now at Thermen Binnenmaas
A day that is entirely yours
At Thermen Binnenmaas you leave the world behind for a while. You drift from one warm sauna to a cool bath, rest on a lounger looking out over the garden, and end the day with something good in the restaurant. No rush, no phone, just calm.
- A heated indoor and outdoor pool, open all year round.
- Twelve saunas and steam baths, from 60 to 90 °C.
- Relaxation temples, gardens and an orangery to recharge.
Everything for a day of full relaxation
A different warmth for every mood
From a gentle sauna to the hottest cabin in the resort, and from a wood-fired outdoor sauna to a cabin where you lie back under the stars. Several times a day our sauna masters pour water with essential oils over the hot stones, releasing a wave of warm, fragrant steam.
See all saunasA day just for the ladies
On the first Monday of each month the spa is open exclusively for women, except on public holidays and during school breaks — then the ladies' day moves a week later.
Ladies' days 2026
A glimpse of Thermen Binnenmaas
Feel the calm before you even arrive. Watch the short film of the resort.
Loved by those who have been
An average of 4.5 ★ on Google, based on 1,834 reviews.
"What a beautiful wellness centre. So incredibly clean! Wonderful pourings, good food, a lovely outdoor area and friendly staff on top of it all."
"A breath of fresh air. A thermen where you aren't fussed over the way you are at the big chains. The restaurant is great too, with fresh, healthy food. We keep coming back."
"Thermen Binnenmaas is a lovely sauna with a beautiful garden, a cool-down pond, ponds with carp, pourings, fine food and staff who genuinely care. Highly recommended."
More relaxation, together
We work with partners nearby, so you get even more out of your visit.
F-S Fitness
Work out at F-S Fitness and unwind with us afterwards. With an unlimited F-S Fitness membership you visit the spa free for 90 minutes a day.
See the combined membershipsResort Valley
Make a night of it. Resort Valley is a holiday home with its own wellness, for when you want the calm to last a little longer.
Discover Resort Valley
Give a day of relaxation
Looking for a gift that really lands? With a Thermen Binnenmaas gift voucher you give calm, warmth and a day entirely to oneself. Available in any amount you like, for a birthday, a thank-you or just because.
You order the voucher easily via WhatsApp or email and redeem it at reception.
Book your moment of calm
Choose your day and time online, or call us for advice. For a treatment or package, it is best to book a few days ahead.