The Kerlingarfjöll area shows all the characters of a matured caldera. Those characters comprise variety of volcanic formations, high energy geothermal spots, rhyolite domes and remains of calderas. The mountains were created by eruptions from a large caldera lying under the mountains, the caldera still considered as active, although it has been silent for tens of thousands of years. Age analysis of the summits, done in 2005 indicates that the oldest mountain is the 336.000 years old Draugafell on the SA side of the area, but the youngest is the 79.000 years old Fannborg. The youngest remains of volcanic activity are the lava field Illahraun or Seturhraun, which lies to the east of Kerlingarfjöll and is as young as 10.000 – 15.000 years old.
Most of the mountains in the area, are created by sub glacial volcanic activity, with only two summits showing signs of having reached above the surface of the ice age glacier at the time of eruption, those are Mt. Loðmundur and Mt Höttur. Loðmundur which stands almost as a separate mountain to the east of the main cluster is a typical plate mountain with a flat well shaped top rocky upper slopes but Höttur being more irregular, but with clear rock formations at the top. Loðmundur, is a combination of two words, “loðinn” meaning hairy and “mundur” which as a second part of a name means guardian, whereas the word Höttur means headgear.
The cluster is usually divided into two main sections, Eastern and Western mountains. The main summits of the eastern mountains are Mt Fannborg, Mt Snækollur, Mt Loðmundar. Mt Snækollur, which is the highest peak in Kerlingarfjöll is also counted as one of five best known stratovolcanoes in Iceland (others being Snælfellsjökull, Snæfell, Hekla and Eyjafjallajökull). Largest summits in the western mountains are Ögmundur and Höttur.
In Kerlingarfjöll there are three separate geothermal areas, Upper Hveradalir, Lower Hveradalir and Hverabotn. Hveradalir means a valley of hotsprings. Lower Hveradalir valley is the main attraction of Kerlingarfjöll, located approx. 5 Km from the Resort, and can either be reached by walking the hiking trail from the resort, or by driving towards Mt. Keis from where there is only few hundred meters walking into the valley.
Hveradalir are most picturesque and with its variety in colours and landscape formation, it offers a very special mixture of geological formations, glaciers, arctic formations and steam springs. As this is an area with retreating glaciers, the landscape also includes hills that are thawing and gliding downhill, offering unique opportunity to see landscape being formed.
During centuries Kerlingarfjoll were viewed as remote and not so friendly place, named as Bad Weather Mountains. Kerlingarfjöll were neither visited nor explored, although the nearby Kjölur area or rather the Old Kjölur Road served as one of the main connections between North and South Iceland. The road or rather the track was on the western side of the Kjölur Area Passing Hvítárnes hut and from there to Hveravellir.
The first sources of information on the area came around 1890, when scientists, both Icelandic and foreign started to visit the mountain area. In the 1930ies the Kjölur road was developed, primarily to transport fence material to lay fences used to separate sheep’s from crossing the area between the north and the south. In 1933 a major step was taken when the bridge over Hvita River was constructed, but the river had always been the most challenging obstacle on the Kjölur road. Three years later or in 1936, it is believed that the first vehicle came to Ásgarður.
Soon after or in 1938, the first hut in Ásgarður was constructed, where the Icelandic Trekking Association built the first half of what we today call the FI house, the first hut on the right when arriving into the valley.
A most important moment came on the 15th of July 1961, when a group of tourists came to Kerlingarfjöll to practice Skiing. This group, which stayed in Kerlingarfjöll for one week, was headed by three gentlemen, Mr. Valdimar Örnólfsson, Mr. Eiríkur Haraldsson and Mr. Sigurður Guðmundsson. Soon after Valdimar, Eiríkur and Sigurður decided to move forward with the idea of establishing a summer ski school in Kerlingarfjöll, which they did in a very successful way. It is the spirit and enthusiasm of these three gentlemen, together with their five other business partners and rapidly growing number of friends and well-wishers that did build Kerlingarfjoll as a popular recreational site during the latter part of the 20th century.
From 1964 to 1990 almost all of the buildings in the valley were built, apart from the FI house as previously mentioned.
By the year 2000, global warming had though destroyed the commercial backbone of the Ski School, the snow was gone, left was and is landscape that compares in beauty, structural variety and colours with most other tourist destination in the Highlands of Iceland.