Farm Grimsstadir and farm Modrudalur are the highest lying farms of the country.  The farm was on the main route between the northern and eastern parts of the country, and its owners were obliged to ferry the travellers across River Jokulsa a Fjollum agains payment until the bridge was built in 1947.  In earlier times, the farm stood 7 km further north, but was moved because of the increasing erosion and sandstorms.  At the turn of the 20th century a new part of the ring road (#1) was opened further south.  The crossing of the road leading to Waterfall Dettifoss still remains in its immetiate vicinity.  The farm is located east of River Jokulsa, about 45 km from Lake Myvatn.  During Catholic times, a prayer chapel stood at Grimsstadir, and it has long been a weather observation station.