France

Gouffre de Padirac
This enormous 75 metre deep chasm forms the entrance to France's most visited show cave, which is accessed via the many flights of stairs seen here (455 steps in total), or by using the lifts. A 1½ hour guided tour starts at the entrance by the yellow sign, and includes a 700-metre boat trip on an underground lake. Unfortunately, photography inside is strictly forbidden, solely to preserve the sale of post cards.
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