Tvígígahellir cave
This 15 meters long cave is in Eldvarpahraun lava field in Reykjanes peninsula, not far from the Blue Lagoon. Eldvarpahraun lava field was formed about 2200 years ago and is around 19 square kilometers big. Tvígígahellir cave is actually connecting two craters and gives a possibility to see how magma was flowing around the craters during the eruption.
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