Fagradalsfjall is a Pleistocene table volcano (tuya) on the Reykjanes peninsula. After 800 years without volcanic activity in the area, the volcano erupted in 2021, producing basaltic lava fountains and flows from March to September. It was the first of a sequence of eruptions, and might have initiated a new phase of activity on the peninsula, continuing for decades or even centuries. This picture shows a warning sign in front of the terminus of a lava flow.