Ponor Fortresses is one of the largest karst complex in Romania, located in the Apuseni Mountains, in the Padis area.
Also called the Everest of Romanian speleology, the karst complex of the Fortresses of Ponor was first mentioned in 1886 by Sandor Nagy. In 1929 R. Jeannel and Emil Racoviţă investigate the entry zone. The first 300 m of the active gallery were explored by e team of the Institute of Speleology in Cluj in 1949. Since 1951, AS Army team of climbers led by Emilian Cristea from Braşov, joins them. A French Speleology team also competes. The active gallery is explored in several expeditions. In 1957 the final siphon is reached. During two other expeditions in 1972, the climbing team of AS Army-Brasov, finally succeds in climbing the last wall over 100 m high, without finding a sequel. Speleologists from Stei are those who have eliminated many questions of the cave´s map. Explorations continue nowadays.
Padiş Plateau is a closed hollow where the surface water is almost absent, being drained entirely underground in the valleys of Boga and Galbena. Only eight pools communicating underground were identified. The area is rich in karst formations, the caves of the Lost World, Barsa Glacier, Rădeasa Canion, Caput Cave. There are several gorges: Galbenei Gorge, Somesul Cald Gorge, Ruginoasa etc.