Volcanic plugs of Iceland

(, regionally also ) is a 15 m high basalt stack along the eastern shore of the Vatnsnes peninsula, in northwest Iceland.

thumb|right|300px|Borgarvirki thumb|right|300px|View from the top of Borgarvirki Borgarvirki lies between Vesturhóp and Víðidalur in the north of Iceland, and at 177m above sea level it dominates the surrounding region. Made out of basalt strata, it has been used as a fortress. Borgarvirki is a natural phenomenon, altered by humans in earlier centuries. In 1949, Borgarvirki was renovated by workers who installed a granite lintel at the main entrance.

thumb|right|Londrangar view from Malarrif thumb|Londrangar Cliffs in Snaefellsness thumb|Lóndrangar, view from the road The Lóndrangar () are a pair of rock pinnacles in Iceland. They are volcanic plugs of basalt, that have been hewn out from softer surrounding rock by erosion. At 75 and 61 m tall, they are a singular sight, rising above and outside the ocean front due east across from Malarrif and some 10 km from Hellnar, on the southern coast of Snæfellsnes peninsula. History has it that the taller of the cliffs was ascended in 1735, while the smaller one was not climbed until 1938