In the land of Efra-Hvol you can find three man-made caves collectively called Efra-Hvolshellar, which translates as Upper-Hvol Caves. They are dug into a rather coarse breccia that most likely originated from tillite deposits. The lower part is more fine grained showing a combination of horizontal, cross-bedded and prograding strata. There are three Upper Hvol Caves, two of which are joined together where the third considered to be the 2nd longest man-made cave in Iceland, measuring some 45 metres in length. However, because a section of the roof collapsed about 100 years ago, one can only go a third of the way into the cave. The Upper-Hvol Caves are a protected natural site.
Gluggafoss (Window Falls), also known as Merkjárfoss. The Merkjá River has several beautiful waterfalls, but the most outstanding is Gluggafoss. It has formed tunnels and grooves through the soft rock and a series of ‘windows’ in the tunnels, thereby earning the name ‘Gluggafoss’.
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