Bunker sauna

We warmly welcome You to enjoy our atmospheric sauna, at the historical and scenic Kuninkaansaari island of Helsinki!


Kuninkaansaari island's wood-heated sauna - also known as "The Box" - is located next to Sand Cove, near the old Officer's House. The concrete bunker has been used as a sauna at least for 75 years, since the early 1940s. The sauna has been used primarily by the island's military personnel and their families. Now, visitors to the islands also have the opportunity to enjoy the rugged but charming Kuninkaansaari Sauna.


If you are looking for a modern, freshly painted, decorated and up-to-date urban sauna, you are probably in the wrong place. You can hardly find a straight or flat surface from the Kuninkaansaari Sauna, but a scuffed space with a special personality. Its long life and history can be seen in the jagged surfaces of the walls, the warm twilight of the changing room, the surrounding nature and the smooth cliffs with their old writings.


With the exception of some necessary renovations, the sauna has been kept as it has been for decades. The bumps and the crooked roof are the essence of The Box. This sauna is for those who do not care about the occasional leafs in the water of the well and who enjoy the atmosphere of the wood-heated sauna and the amazing soft steam without any additional disturbance.


The Sand Cove's cliffs are 50 metres away from the sauna and it is also possible to swim there. The sandy beach is around 100 metres from the sauna.

Sauna is available during the summer season from the beginning of May to the end of September.

"Aivan mielettömän ihana symppis Koppi-sauna!"


Prices in 2021 (including VAT)

For season 2022, the day sauna (12:00 - 15:00) can be booked on Saturdays and Sundays from the beginning of May to the end of September. Price for day sauna is 165,00€ (3h). Check for available times in the online store's booking calendar.

There is accommodation on the island, which is why the sauna shift between 6 pm and 10 pm is always reserved for accommodation guests only.

Good to know

  • You will receive written instructions in your email regarding your arrival and use of the facilities week before of your stay.

  • The sauna heats up in about an hour, sometimes faster in the summer time.

  • Firewood can be found in the dressing room.

  • We use carried water from the well, which is about 100 meters away. The buckets can be carried smoothly with the milk carts. Do not use seawater at all in the sauna.

  • The sauna can accommodate 5-6 persons at the same time. Facilities are not suitable for large groups.

  • No alcoholic beverages are served on the premises. Bring your own alcoholic beverages and refreshments.

  • Swimming on your own risk at the nearby beach. You can find the rocky beach by following the path leading from the sauna.

  • The sauna has a fridge and an outlet that can be used for charging a phone etc.


You should take with you


  • Towel

  • Swimsuit

  • Beach sandals or other footwear for walking on the path and beach

  • Something to drink

  • Soap / Shampoo (limited amount available at the sauna)


Make a booking


Booking in 2022


For the time being, the sauna can be booked as follows:

  • Freely bookable to all, Saturday and Sunday from 12:00 to 15:00

  • Monday is a maintenance day, no reservations

  • Accommodation guests, Tuesday to Sunday from 18:00 to 22:00

Make a booking by going directly to the booking site. Sauna is available from the beginning of May until the end of September.




Water buses will operate to the Torpedo Bay pier. From Vallisaari to Kuninkaansaari you can walk along the embankment. It is advisable to book time for about 15-20 minutes of walking from Torpedolahti (25-30 minutes from Luotsipiha). You can also come to Vallisaari with your own boat.


Phone +358 (0) 40 764 9766

(Mon-Fri 10am-5pm, Sat-Sun 11am-4pm)

Helsingin Saaristoretket

Business ID: FI27652404