Kaylaka

Kaylaka (Кайлъка) is a large park and protected area south of Pleven, Bulgaria, situated in a Karst valley. The park is spread over 10 km² and is surrounded by sheer cliffs that suggest favourable conditions for rock climbing. The ruins of the Roman fortress of Storgosia are located in Kaylaka, as well as ponds and reservoirs with boats and pedalos, a swimming pool, hotels, cafés, restaurants, discotheques and playgrounds.
http://en.wikipedia.org/wiki/Kaylaka