Mts Kerlingarfjoll are a cluster of mountains on the south side of Kjolur, a short distance to the SW of Hofsjokull glacier, on the water divide of the rivers Hvita and Thjorsa. They form a group of peaks and ridges that cover an area of approximately 150 km2. The highest peaks are around 1500 m above sea level. The rivers Asgardsa, which flows into Hvita, and Kisa, which flows into Thjorsa, nearly divide the mountains into two clusters, the western and eastern mountains. The name of the mountains comes from Kerling, a 25-meter-high hyaloclastite pillar that stands in a light-colored rhyolite scree southward of Kerlingartindur (Kerling peak) on the western side of the mountains. The eastern mountains form the highest and most fearsome part of the area. The highest peaks are Lodmundur, 1432 m, and Snaekollur, reaching a height of 1477 m. Kerlingarfjoll boast of some of the most powerful geothermal areas in the highlands, located in the middle of the mountain cluster and bordered by several peaks that are believed to be the remnants of the edges of a large, ancient caldera. Among these are Maenir, Hveradalahnjukur, Fannborg, Hottur and Ogmundur. The slopes of some of the mountains have minor glaciers that have shrunk considerably in recent decades. The riverbed of Asgardsa is a narrow chasm at the upper end which opens into a small valley shortly before the river flows into Jokulfallid. Hveradalir are divided into Vesturdali, Middali and Austurdali (west, middle, and east dales). The hot springs there are fumaroles or mud pots. Considerable continuous transformation in rock and strata characterizes the hot spring areas. In addition, specialized flora grows near the springs.
A. NEDRI-HVERADALIR – 10 KM The route is marked. Altitude increase is around 400 m. Difficulty level red. The trail ends north of Nedri-Hveradalir, a short distance from the Snorrahver fumarole on the Hverdalahringur (see route F). Service Centre Asgardur (N 64° 40.998 V 19° 17.985) Hverdalahringur (Snorrahver) (N 64° 38.96 V 19° 18.139) The route begins at the service centre in Asgardur and passes over the Asgardsa bridge. Once it reaches the other side, there is a marked hiking trail up the esker (see trail) and from there up the slope past Hveradalahnjukur on the left side. This is a beautiful hiking route and directs the traveller up to NedriHveradalir, where it meets a hiking trail that runs in a circle in Nedri-Hveradalir (see Hveradalir circle). On the way, it is a good idea to take a break in good weather and look to the north, as the views are open to both the north of Kjolur and to the west over Kerlingarfjoll and toward the lake Hvitarvatn. From this route, there is another marked route that takes us around Maenir (see Maenir circle). This route can be travelled by most hikers and is popular among the visitors to Kerlingarfjoll.
B. ASGARDSFJALL – 2.5 KM The route is marked. Altitude increase is slightly more than 200 m. Difficulty level blue. Expect the hike there and back to take 1–2 hours. The route to the Asgardsfjall mountain is easy. The route begins at the service centre and lies between the summer cottages on the south side of the service centre and toward a small gully. This is used as a way up and onto the track that leads up onto Keis. The track leads up the mountain to the south-east. It then turns left toward the north and along the mountain ridge. There are quite good views from Asgardsfjall over northern Kjolur and toward Hofsjokull. In addition, there are excellent views over the eastern mountains in Kerlingarfjoll as well as to the northwest over Kjolur toward Hrutfell and Hvitarvatn. There are interesting hyaloclastite formations at the top of the mountain.
C. SKUGGAFOSS – 15 KM The route is not marked. Altitude increase is around 100 m. Easy walk. Difficulty level blue. Expect the hike there and back to take 5–6 hours. Skuggafoss (N 64° 42.424 V 19° 11.257) Skuggafoss falls down a narrow ravine in the Jokulfall to the south by Blagnýpa, a short distance from Hofsjokull. The trail lies for the first 1.5 km along the track to Setrid. Several streams need to be crossed to begin with, but after that, the route lies to the east upward and along the Jokulfall. After approximately 5 km, hikers reach Skuggafoss, where it is a good idea to have a seat and enjoy the beauty of the landscape near Hofsjokull. The waterfall is spectacular and beautiful as it falls down the narrow ravine.
D. HVINUR – FOSSROFUR – 15 KM The route is marked. The altitude increase is approximately 40 m. Easy walk. Difficulty level blue. Expect the hike there and back to take 2–3 hours. The bridge on Jokulfallid (N 64° 42.19 V 19° 23.7) The route starts at the bridge where the Kerlingarfjoll jeep track and the Leppistunguleid track meet. The route is along the Jokulfallid from Hvinur to Fossrofur. Jokulfall flows in huge canyons from the Hvinur waterfall down to Fossrofur. The route down is on the north side of Jokulfallid. The hike is along the river to Gigjafoss waterfall. This is a good place to take a break and have a look at this lovely waterfall where Blakvisl and Jokulfall meet. The next part of the hike is along the Jokulfallid, south of the airport, and down to Fossrofur. The section down to Fossrofur leads us past Skipholtskrok, one of the locations searched in hopes of finding the Holy Grail that was used in the Last Supper.
E. KERLING – 7.5 KM (FROM LEPPISTUNGULEID ROUTE) The route is marked. Altitude increase is around 150 m. Easy walk. Difficulty level blue. Expect the hike there and back to take 2–3 hours. Parking area at Skeljafell (N 64° 39.489 V 19° 24.096) Kerling i Tindi (N 64° 38.164 V 19° 23.193) Drive down a rough, marked track (Leppistunguleid) to Fremri-Asgardsa and to Skeljafell. The parking area is approximately 200 m from the river. From the parking area, the route lies between Skeljafell and Tindur, a marked hiking route to Kerling. Kerling is a tuya (table mountain) approximately 24 m high which the Kerlingafjoll range is named after. There is something special about standing by the tuya and reminding oneself of folk tales about a troll woman that was turned into stone. There are two options for the way back. It is possible to walk a marked route up to Skjeljafell, or one can go on the west side and return by Leppistunguleid back to the parking area. If the route up to Skeljafell is selected, an approximately 250 m elevation is added.
Text from Umhverfisstofnun- Environment Agency of Iceland
and picture and information from nat.is