Yazlık Ilıcası Termal Tesisleri

Yazlık Ilıcası Termal Tesisleri is on Osmanlı Caddesi in the Yazlık Yeni neighbourhood of Gölcük, a district of Kocaeli. The building around the spring dates from the 2nd century AD, in the Roman period; the vaulted stone and brick structure, which served the settlements south of Nicomedia (İzmit), remained in use in the Byzantine and Ottoman periods. In service since 25 May 2013 following restoration by Gölcük Municipality, the facility is one of those run by GÖLAŞ, the municipal company.
There are separate spa sections for women and men; each has a thermal pool, a hammam, a jacuzzi, a sauna, a steam room and a children's pool. There are no sessions or bookings for the pool areas, and use is limited to three hours. The water emerging from the spring is between 22 and 32 °C; it is a mineral water that also contains a small amount of sulphur.
There are also family rooms that families and couples can rent for two hours: the VIP rooms have a jacuzzi, a hammam, a sauna, a navel stone (the heated marble platform) and a rest room, while the standard rooms have a jacuzzi and a hammam. Booking is compulsory for the family rooms, and couples are asked for ID or their family register booklet. The facility also has a car park, a prayer room, snack bars and a lift for disabled visitors.
The facility is open from 08.30 to 22.30 from Tuesday to Sunday and from 13.00 to 22.30 on Mondays. Swimwear and a swimming cap are required in the pools; you can bring your own towel and slippers or buy them at the facility. Children under 11 are admitted only with an adult, and phones and cameras are not used in the women's section.