Ubajara, Brazil
Gruta de Ubajara (English: Ubajara Grotto) is a limestone cave, located within the Ubajara National Park, near the city of Ubajara, in the foothills of the Serra de Ibiapaba, Ceará, Brazil. Its sequence of nine halls has a length of 1,120 m (3,674.54 ft), of which 420 m (1,377.95 ft) are lit trails.
The site can be accessed either via a cable car which descends over a 535 m (1,755.25 ft) deep depression, or on foot along the 4 km (2.49 mi) long Cafundós trail.
Listen to the audio guide for Gruta de Ubajara Free on WIP — starts by itself when you arrive, even with the screen off