One of the famous hot springs where people can take a bath is at Landmannalaugar. It is found in the middle of a polygon, with Hekla and Laki at each side.
Landmannalaugar are found at 64°N, the same parallel as Hekla and Laki. The latitude is also the central axis of the SISZ, extending from Hveragerði to Hekla. Repeatedly, we can trace the NS and EW-axis of different polygons. The ductile part of the tectonic plate, reaching 120 km down where convection of mantle starts to take place, gives way to the tectonic drift and breaks along the middle axis from one corner of the polygon to the other. Therefore this is repeatedly seen on the surface.