A 3-week scuba diving trip to the Solomon Islands.
Originally, it was supposed to be a liveaboard trip with my NYC dive shop. (A liveaboard is a small, full service boat on which 8-16 divers live diving locations far away from land.) However, we arrived on to find the boat unable to leave port. After a few days of exploring & diving around the island of Guadalcanal, the liveaboard cancelled the trip.
While most of the divers returned home or flew to countries with which they were more familiar, I arranged to island hop & dive 3 different local islands: Munda, Lola & Gizo. A stranger who I met through the boat decided to join me on this adventure.
It ended up being one of the best trips I've ever taken.