Beware, this is not for the faint hearted! Journey deep into the heart of a Welsh mountain for a unique adventure challenge and experience a whole new world while taking on extreme challenges. Meet an intrepid guide for a briefing and once kitted out, embark on an epic journey which involves negotiating secret subterranean tracks, tackling traverses, crossing decaying ancient bridges, climbing up unspoiled rock faces, abseiling, whizzing across the world's longest and deepest underground zip line - and last but not least, experiencing the world's first underground freefall. Stand at the edge of the ledge and plummet into a 70 foot abyss, falling at incredible speeds - but don't worry, the brake is applied before you reach the ground