Iceland Travel GuideLOCAL TRAVEL AGENCY IN ICELAND
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Iceland Travel GuideLOCAL TRAVEL AGENCY IN ICELAND
My trip
Talk to a local
Askja is a vast volcanic caldera in the Dyngjufjöll mountains of Iceland's central Highlands, within Vatnajökull National Park. It holds the lake Öskjuvatn and, beside it, the smaller, warm Víti crater. Askja lies about 100 km south of the Ring Road by mountain track, a drive of 3–4 hours each way from Mývatn in a 4x4, and a two-day trip from Reykjavík. It is free to visit, open only from about late June to early September, and most visitors spend half a day on the walk to Víti and back.
Askja is one of Iceland's largest active volcanic systems. The caldera covers about 50 square kilometres in the Dyngjufjöll massif, and inside it a second, younger caldera collapsed after a catastrophic eruption in 1875. That eruption dropped more than a centimetre of ash over roughly 5,000 square kilometres of eastern Iceland, ruining farmland and forcing some families to emigrate. The collapse left behind Öskjuvatn, a deep, cold lake covering about 11 square kilometres and reaching 217 metres deep, Iceland's second-deepest lake after Jökulsárlón.
Beside it sits Víti, a smaller explosion crater holding milky-blue, mineral-rich water that is noticeably warmer, typically 20–30°C. From the Vikraborgir car park, a marked trail leads about 2.5 km to the rim of Víti, a walk of 30–40 minutes across stark, otherworldly volcanic ground. The descent into the crater itself is steep and can be slippery when wet, and swimming is sometimes restricted by rangers depending on conditions.
Askja is really several calderas, one inside another. The largest is about 8 km across and is thought to have formed in a big explosive eruption around 10,000 years ago, at the end of the Ice Age. The mountains around it were built up by eruptions under the Ice Age glacier, and the highest point of Dyngjufjöll reaches just over 1,500 metres. All around lies Ódáðahraun, the largest lava desert in Iceland, which covers several thousand square kilometres of the north-eastern Highlands.
The volcano is still active. Its last eruption was in 1961, and since 2021 the ground inside the caldera has been rising slowly, which scientists are watching closely. For visitors this means following the rangers' advice and checking for any restrictions before you set out.
On 28–29 March 1875, Askja produced one of Iceland's most destructive eruptions in modern history, throwing rhyolitic ash and pumice over a huge area of eastern Iceland. Farms were buried, livestock died, and the hardship that followed pushed a wave of Icelanders to emigrate to North America. The eruption also emptied out part of the magma chamber beneath the volcano, and the ground above it slowly collapsed to form the caldera that now holds Öskjuvatn.
Askja is only reachable by F-roads, which are closed outside roughly late June to early September and always require a 4x4. Check road.is and a ranger or tour operator for current conditions before setting out, and never attempt a river crossing you are not confident about.
This is the easier of the two routes, by way of Möðrudalur. All of it beyond Route 901 is for 4x4 vehicles only.
Fords change with rain and snowmelt. Stop at the ranger station at Dreki or ask a passing ranger about the rivers, and turn back if you are not sure.
The two lakes sit side by side but could hardly be more different.
There are no changing rooms, no showers and no lifeguard. The path into the crater is steep clay and gets very slippery in rain.
Outside the short summer season, Askja is accessible only with specialist super-jeep operators equipped for winter Highland travel.
There are basic toilets near the Vikraborgir car park in season. There is no shop, café or fuel at Askja itself; the nearest services are back at Mývatn.
There is no accommodation inside the caldera. The Dreki huts and campsite at Drekagil, about 8 km from the car park, are the closest place to sleep and give you an early start on the walk to Víti. Otherwise most visitors base themselves at Mývatn, or at Möðrudalur, which has a campsite and is about 2.5 hours' drive from Askja.
Yes, with a proper high-clearance 4x4 and experience with unpaved F-roads and river crossings. Many visitors prefer a guided tour from Mývatn instead.
The F-roads leading in are typically open from late June to early September, weather and river conditions permitting.
Sometimes. Rangers may restrict swimming depending on conditions, so check locally before planning to swim.
About 2.5 km each way from the Vikraborgir car park, roughly 30 to 40 minutes on foot.
No, it is free to visit, though reaching it requires a 4x4 or a guided tour.
In 1961. The best-known eruption was in 1875, which formed Víti and led to the collapse that now holds Öskjuvatn.
About 217 metres, which makes it the second-deepest lake in Iceland after Jökulsárlón.
Drive east on the Ring Road, then Route 901, the F905 and the F910 to the Dreki huts, and finally the F894 to the Vikraborgir car park. Allow 3–4 hours each way in a 4x4.
Tours and trips that include Askja, booked directly with a local travel agency in Iceland.
