Jokulsargljufur

Jokulsargljufur is the northern arm of Vatnajokull National Park, a canyon carved by catastrophic glacial floods along the Jokulsa a Fjollum river. It runs about 25 km from Dettifoss down to Asbyrgi, a horseshoe-shaped depression that Norse settlers believed was the hoofprint of Odin's eight-legged horse Sleipnir. Geologists say it was cut in a matter of days by a jokulhlaup roughly 8,000 years ago. The area was a separate national park from 1973 until 2008, when it merged into Vatnajokull. It is the wildest, quietest gateway of the park.

The canyon rewards a full day and its own car. Start at Dettifoss west bank on paved Route 862 for the most powerful waterfall in Europe by volume, then loop to Selfoss upstream and Hafragilsfoss downstream. Cross to the east bank via Route 864 (gravel, closed in winter) for a closer, wetter Dettifoss viewpoint. Continue north to Hljodaklettar echo rocks with their columnar basalt swirls, then finish at Asbyrgi to walk the flat 1 km trail to Botnstjorn pond under the cliff walls.

Base at Myvatn or the small town of Husavik for two nights. Fuel up at Reykjahlid; there is no petrol between Myvatn and Asbyrgi. Bring a mid-layer even in July; the canyon rim can be windy and rain-lashed. The west bank of Dettifoss is accessible year-round; the east bank sees the classic Prometheus film view but the gravel road is rough. Combine with a whale-watching trip from Husavik or the Myvatn Nature Baths for an easy two-day loop.

Trail by trail, this is what the day actually asks of your legs. From the Dettifoss west car park a graded gravel path drops roughly 1 km to the railing above the lip, ten to fifteen minutes down and a slower fifteen back up over one stepped section. Selfoss sits another 1 km upstream along the same rim path, about twenty minutes each way, and is the better photograph of the two on a flat grey day because the water spreads across a wide basalt shelf rather than vanishing into spray. At Vesturdalur the Hljodaklettar loop runs about 3 km, an hour and a quarter, past the fanned columns nicknamed Kirkjan and Kastali; the Raudholar red-crater extension adds a climb and another hour. At Asbyrgi, walk the boardwalk to Botnstjorn first, then take the Eyjan trail, around 5 km and two hours, for the view straight down the horseshoe. If time is short, skip Holmatungur.

Getting there means driving, and there is no honest way around that. From Reykjavik it is roughly 540 km on Route 1 to the Route 862 junction, six and a half to seven hours; from Akureyri it is about 165 km and two hours, which is why most visitors rent the car there. The 862 turn-off is around 25 km east of Reykjahlid, and the paved section runs 30 km north to the large Dettifoss west car park with its toilet block. The east bank car park is about 19 km along gravel Route 864, which leaves the Ring Road further east. Asbyrgi is reached from the north on paved Route 85, an hour from Husavik. No Straeto service comes near the canyon; summer Diamond Circle coach tours from Akureyri and Husavik run ten to twelve hours and cost from roughly ISK 25,000. Rent, do not wait for a bus.

Costs are almost entirely fuel and tyres. Entry is free, the Gljufrastofa exhibition at Asbyrgi is free, and every car park in the canyon is free, so the loop from Myvatn out to Dettifoss, up to Vesturdalur and Asbyrgi and back along Route 85 comes to about 200 km, or ISK 4,500-5,500 of petrol at current pump prices of roughly ISK 310-330 a litre. Add gravel and ash damage cover on the rental, typically ISK 2,000-3,500 a day, which is worth buying before you touch Route 864. Camping at Asbyrgi or Vesturdalur runs around ISK 2,000-2,500 per adult a night with children free. Nothing else inside the park takes money: no cafe, no ticket, no audio guide. Buy lunch and a thermos in Reykjahlid before you set out and you will spend nothing between the Ring Road and Asbyrgi.

Timing matters more here than in most of Iceland because the coaches all arrive in the same four-hour window. Be at the Dettifoss west railing before 09:30 or after 18:00 and you may share it with two cars; between 11:00 and 15:00 in July the car park fills and the viewing platform queues three deep. Asbyrgi empties after 17:00 and is at its best under the midnight sun in June, when light still touches the 100 m cliffs at 23:00. July and August are the only months with the whole 862 gravel stretch reliably open. September brings gold birch in Asbyrgi and almost no one. From October to April expect the west side only, four to five hours of daylight in December, an icy spray-glazed path that wants microspikes, and closed facilities. May is a gamble: check road conditions before committing.

This suits drivers, walkers and anyone happy to be cold for a view. Families do well at Asbyrgi, where the Botnstjorn boardwalk is flat, short and sheltered, and where the campsite has real toilets; Dettifoss is the opposite, with unfenced cliff edges either side of the built platforms and wet rock, so small children need holding the whole time. Wheelchair users can reach the Gljufrastofa exhibition and roll part of the Asbyrgi trail on firm surfacing, but the Dettifoss west path has a stepped section and no accessible alternative. Teenagers usually take to the Eyjan climb rather than the viewpoints. On a wet, windy afternoon the canyon is genuinely miserable at the rim, and the honest move is the Gljufrastofa exhibition then the Myvatn Nature Baths. With a one-hour gap in your schedule, do not start: five hours is the realistic minimum.

Fold in the sights on the drive rather than adding a second day. Namafjall and the Hverir mud pots sit five minutes off the Ring Road beside the 862 junction, Krafla and Viti crater are fifteen minutes north of it, and Grjotagja cave is on the way back into Reykjahlid; Kopasker is 35 km north of Asbyrgi if you want a shop and a harbour. Now the caveats. Dettifoss is powerful, not pretty: the water is grey-brown with glacial silt and photographs poorly in flat light, and the noise is the point. The east bank Prometheus view is oversold given the corrugated 40-minute drive each way, and small rental cars pick up punctures on it. Hljodaklettar barely echoes. There is no cafe, no shelter and patchy phone signal along the whole canyon, so carry food, water and a paper map.

Hours & entry

Always free; parking free at all viewpoints

Trails open year-round 24/7 · Asbyrgi visitor centre 10:00-17:00 May-Sep · Route 862 gravel section closed in winter

What to see

• Dettifoss west bank viewpoint — End of paved Route 862, 30 km from Ring Road
• Asbyrgi horseshoe cliff — Botnstjorn pond, 1 km flat trail from Asbyrgi car park
• Hljodaklettar echo rocks — Vesturdalur car park, 12 km south of Asbyrgi on Route 862

Tips from the ground

• Approach Dettifoss on Route 862 from the north (paved, faster) rather than the south
• The east bank of Dettifoss (Route 864) is unpaved and requires care in a small rental car
• Do the Asbyrgi rim walk at sunset in June for pink light on the 100 m cliffs