Access is difficult – 4m long ladders and ropes required to negotiate through a short (25m) but cumbersome dry cave session to reach the water.

Alviela is one of the major springs in Portugal and was once the major source of water in Lisbon; today less than 10% of Lisbon’s water consumption comes from Alviela. The entrance is situated in a Park area which is a popular swimming venue for the local population. There is also a camping site, restaurant and toilets on-site. The local municipality built a science exhibition pavilion on site, which features a virtual 3D trip through the cave system with explanation about cave formations and water cycles.

The cave drops quickly to 30m (around 100m penetration) with most of the passages located between the 40 and 55m depth range. The "supposed" main tunnel then drops steeply down to 125m and continues according to the last 2002 exploration effort (SPE and FFESSM). Recently (2007) Jeróme Meynié supported by SPE, reached 130m and returned with news of a blocked passage, and silt on the floor of the high flow main tunnel. Lots of exploration opportunities exist in this beautiful cave.