1 Langjökull Glacier, Iceland
Each year at Secret Solstice Festival in Iceland, patrons are given the opportunity to participate in a once-in-a-lifetime experience. In 2015, the festival put on a special event described as “the world's only party inside a glacier” that saw Totally Enormous Extinct Dinosaurs and Artwork play a back-to-back set inside the Langjökull Glacier. Due to the event's exclusive nature, only 70 guests were allowed to attend. In terms of throwing parties in natural locations, Secret Solstice is leading the charge both with their glacier party and also with a nearby volcano which festival attendees are invited to dance within. Read further down this list for more details.