Quilotoa, Ecuador has got to be one of the most beautiful places on Earth. When this volcano collapsed, it eventually left an crater lake. Quilotoa is located at almost feet, so it's extremely cold, but the trip is well worth it.
This is probably my dumbest move traveling - jumping off a 35-foot cliff at Rick's Cafe in Negril, Jamaica. Part of the problem is the height. The other problem is that jumpers come dangerous close to the cliff during the descent. In fact, some people have actually hit the wall. The entry wasn't pleasant, but I walked away without any injuries. - 2006