The rhyolite laccolith Sandfell /743m) is located south of the Faskrud Bay in Eastern Iceland.  Some of the basaltic strata were lifted during its creation 14-16 million years ago, but in other places, especially in the southern slopes, the basaltic strata are intact and disappear under the slopes.

The laccolith is about 600 m thick and was pushed through 500 m thick strata of basalt.  At the time, the so-called Reydarfiord Central Volcano nearby was at its peak of activity.  The Sugar Loaf of Rio de Janeiro is of the same kind.  The most popular trail to the top of Mt Sandfell is approached from the southeast.