An award winning film (2010 BUIF- Professional DVD - 1st prize) by David Perez, 35 (quality) minutes, Spanish and French subtitles. Pozo Azul is a large cave resurgence in Northern Spain. Since 2001 a British lead team has systematically explored and extended the immense Sump 2. Each expedition has required innovative modifications to rebreathers, DPV's and habitats to enable exploration to progress. The video covers the 2009 explorations at Pozo Azul, when the 5160m long 2nd sump was finally passed. This involved dive times in excess of 12 hours.