G-17 The geosite is situated at the 17th km of the road between Zonguldak and Ereğli, close to the seaside. The “Ilıksu” means warm or mild water in Turkish, therefore the Turkish name of the site describes thermal water. The temperature of the water is about 29.5 °C and the discharge is ca 23 liters per second. The spring water comes with a strong flow from the boundary of the Carboniferous aged Alacağzı Formation and the Cretaceous aged İnaltı Formation. According to the studies, there is no chance to increase the water temperature with technical operations due to geological conditions.