Skip to content

FUENTONA DE MURIEL 360 – Spain – 2021-2022

The Area

The Fuentona de Muriel surgency is enclosed in a Natural Reserve in the province of Soria within the autonomous community of Castille y León in Spain. Access to this protected area is highly regulated with special permits required to access the cave.

This cave is “famous” as it was featured in the TV series Al Filo de lo Imposible (On the edge of the impossible) in the early 2000’s.

The cave is a surgency for a medium flow river which flows through a limestone canyon it has cut through. After heavy rains in the winter, the cave is known to have very strong flow as the surrounding valleys direct the water straight into this aquifer.

The parking lot is located at about 800m via a well-maintained path which complicates logistical matters. Despite this, using some gear carts it typically takes only about 2 to three trips to get the gear transferred. Direct access to the cave entrance can be done exceptionally via 4×4 with special permits and help from the park rangers.

The Project

The project’s objective is to create a high-resolution 360 video of different parts of the cave to then have them on display at the local town hall. In addition, the team will try to continue the work done so far the the Al Filo de lo Imposible team.

The Team

  • Alan Weinberg (Project co-director & Exploration Diver)
  • Juan Alberto Achica (Project co-director & Exploration Diver)
  • Juan Carlos Albert (Suport Diver)
  • Iñaki de Santos (Exploration Diver)
  • Álvaro López (Exploration Diver)
  • Juan Alfonso Sánchez (Exploration Diver)

Do you want to join the team? Connect with Alan Weinberg.


May 2021

  • Inspection of the entrance
  • Dive is canceled due to an issue with one of dry suits

September 2021

  • Installation of new cave arrows on main line with exit distance
  • Sump inspection 
  • Video recording

March 2022

Team performs 360 recordings of cave entrance all the way to bypass at -36m.

Project is unfortunately terminated in 2022 due to some political issues.