"One of the most popular caves in Iceland is right next to the Reynisfjara black beach at the foot of the Reynisfjall mountain. It is surrounded by basalt columns and it makes the background of countless of photos of all kinds, from selfie shots to wedding photos.
Where to find Hálsanefshellir cave:
The entrance to the cave is directly from the Reynisfjara black beach. You can park your car at the parking lot nearby. "
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"Hálsanefshellir Cave is a huge sea cave located at the beach close to the small town Vík. The cave is exceptional because of octagonal basalt pillars at the cave entrance. The vertical columns are quite similar to Fingal's Cave on Staffa Island. And the beach in front is the famous Reynisfjara black beach, which consists of the eroded black basalt.
There are actually two sea caves at the beach looking quite similar. Even some websites mix them up. Hálsanefshellir has the pillars on the right, the other cave on the left side of the entrance.
The beach is named after the mountain above, the Reynisdrangar (Three Trolls). It is formed by three huge basalt flows which look like an irregular stack. According to legend, there were three trolls who tried to pull a ship to shore, but took so long they were caught by the sunrise and turned into the three spiky rocks you see today. The mountain has various spots consisting of basalt pillars.
The beach is not only famous, it is also infamous, because it is one of the two beaches on Iceland with dangerous undercurrent. There are actually deaths because of this, in 2017 a family was caught by a wave and the mother was killed. So it is good to have an eye on the waves when you visit the caves. Bathing is discouraged and there is actually a forest of warning signs."
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