Askja is one of the most jaw-droppingly beautiful places in Iceland. This volcanic caldera is located high up in the Dyngjufjall mountains of Iceland’s Central Highlands. Askja’s remote location, inaccessible during the winter months, means it sees relatively few visitors. Those who do make it up aren’t disappointed. Summer in the central highlands is not like summer elsewhere in Iceland.
Askja sits in the rain shadow area of Vatnajökull, meaning that it is relatively dry, as precipitation tends to fall on the glacier instead. But it’s bitterly cold, and you can certainly expect snow. The rewards for intrepid travelers put it on the list of top things to do in Iceland, no questions asked. After all, how many people can say they’ve been swimming in a volcano?
How was Askja formed?
A caldera such as Askja is a volcanic crater lake. It is formed when an active volcano erupts. If a large amount of the underlying magma is ejected, there is nothing to support the volcanic cone immediately above it. This ground then collapses in on itself, leaving a huge hollow, known as a caldera, on the surface.
This is what happened at Askja at the end of the last Ice Age. Askja caldera is located in the Northern Volcanic Zone, one of four such areas on the boundary of the Eurasian and North American plates. This boundary cuts right through Iceland, which explains why there are so many volcanoes. Askja volcano is the highest of the mountain peaks in the Dyngjufjall mountain range, relatively high by Icelandic standards.
The formation of the Askja caldera took place approximately 10,000 years ago. Askja consists of three main calderas, the largest of which is simply called Askja, an 11 km2 (4.25 square mile) lake. An older, much smaller caldera called Kollur lies further to the north. However, it was the eruption of 1875 that totally transformed Askja, creating two of its most famous features: the crater lakes of Öskjuvatn and Víti.
What happened during the 1875 eruption?
On the 28th March 1875, a huge explosive eruption shook Askja, with the resulting column of ash visible from hundreds of miles away. The effects of this eruption were devastating for many people in the east of Iceland. Thousands of tons of ash and tephra were deposited over a wide area, poisoning the land, killing livestock and ultimately forcing many Icelanders to emigrate.
The explosive 1875 Askja eruption occurred in the southeast corner of its caldera, and it led to the formation of a new one. Over the course of the next 50 years, this new caldera filled up with groundwater. As it continued to subside, it continued to grow. This water-filled caldera came to be known as Öskjuvatn – or Lake Askja – and today it is Iceland’s deepest lake, reaching a depth of 220 meters.
The crater Víti was formed by the same eruption, when magma reacted explosively with groundwater, leaving behind a huge crater. Conveniently for today’s visitors, this new crater was formed adjacent to the shores of Öskjuvatn. Today, Askja is still very much an active volcano. It last erupted in 1961, but as recently as September 2021 earthquakes were detected in the area, which were suspected to be a result of magma intrusion.
The NASA Moon Landings
The area surrounding Askja is often described as otherworldly. Its barren lava fields stretch for miles and mountain peaks punctuate the horizon. In the 1960s, NASA used this area as a training base for moon landings. The lunar-like landscape of Askja proved to be the perfect location to prepare astronauts for the conditions that they would encounter. Today, the main exhibition room at The Exploration Museum in Húsavík recounts the story of the NASA training missions in Askja.
How to get to Askja
Getting to Askja is an adventure in itself, a journey almost as memorable as the destination itself. The mountain roads (known as F roads) that lead to Askja are only suitable for 4WD vehicles, so you'll need to rent a 4x4 for your trip to Iceland, ideally one with high clearance. You also need to consider your travel times – the roads are only open in the summer months, typically from the end of June until the beginning of September.
If you are planning to travel to Askja, it’s important to check the weather forecast and the road situation before setting out. The Icelandic Road and Coastal Administration has a dedicated website that provides updated road conditions data in real time, an invaluable tool for anyone traveling in their own rental vehicle. There are two main routes that you can take to Askja, and they both take around 3 hours to reach the ranger station at Drekagil from wherever you turn off the ring road. These are:
- Drive approximately 30 minutes east of Lake Mývatn on Highway 1. From there, take the F88 to Drekagil. The F88 offers spectacular views of Herðubreið mountain, which is sometimes referred to as the Queen of the Icelandic mountains. However, there are several difficult river crossings that you will have to navigate. It is strongly advised to avoid this route unless you’re highly experienced in driving in challenging environments and your 4WD is a more powerful model and has been modified with larger tires.
- The second option is a lot easier. Drive further east on Highway 1 before taking the gravel road 901 and then the F905 for 20 km before taking the F910 for a further 60 km to Drekagil. There are river crossings on this route but nothing as challenging as on the F88 and you will easily be able to do this journey in a standard 4WD vehicle.
Where to go once you reach Drekagil
Drekagil literally translates to ‘Dragon Gully’. As you might expect of a canyon with such a name, the rock formations are truly remarkable. It is definitely worth stopping here to be able to take a short walk into the canyon, where you will find a small waterfall. Drekagil also houses the area’s ranger camp and offers weary travelers the chance to rest and recuperate before embarking on the final leg of their journey to Askja. It is possible to stay here overnight. Basic but comfortable accommodation is provided in several huts on site.
From Drekagil it is a short 8 km drive on the F894 until you arrive at the car park at Vikraborgir. This is the end of the road and the rest of the journey is on foot. From here it is a 45-minute walk to Askja along a relatively flat valley. The walk may be short, but we recommend having good footwear as there is often snow on the path, even in the summer.
What to expect from Víti and Öskjuvatn
As you approach Askja, Öskjuvatn gradually appears in view. On a clear day, the mountains are perfectly reflected in its crystal-clear waters, providing one of the most iconic views in Iceland. It is hard to imagine that this tranquil and serene sight was the result of a violent and explosive eruption less than 150 years ago. It is possible to walk to the shore of the lake (you can go swimming in it if you’re hardy enough).
The sheer scale of Víti quickly becomes apparent. The explosive crater is about 100 meters (328 ft) in diameter. The geothermal milky blue water that sits in the crater is reminiscent of the famous Blue Lagoon Spa and looks just as inviting. The steep-sided crater walls are a most impressive sight, though the overwhelming stench of sulfur is considerably less pleasant.
Víti’s almost vertical crater walls require some care. In wet conditions, it can be treacherous and in such circumstances, it’s not advisable to descend to the water’s edge. If you are in doubt, check with a ranger. Note that as you approach the edge, there are no safety rails here – in fact, the area remains blissfully free of the usual trappings of tourism.
If you want to swim, follow the path and follow the trail down to the crater. The temperature hovers around the 22ºC mark. In contrast to the way down, the banks of the crater are actually surprisingly shallow, making it easy to go in and out of the water.
Not far from Víti, overlooking Öskjuvatn, stands a monument to two German scientists who mysteriously vanished without trace whilst exploring the area in 1907. Though their disappearance remains a mystery, it’s possible that a landslide may have caused a sizable wave that engulfed their small boat. It is a poignant reminder of the dangers inherent to visiting an active volcano.
The road might be challenging, but ticking Askja off the things-to-do-in-Iceland list is definitely more than worth it. Askja is one of the most stunning locations in Iceland, and we think its incredible beauty, along with the thrill of driving there, will be an experience that will live long in your memory.
Rent your own car in Reykjavik or book one of the many Askja tours that depart from Reykjahlíð or other places in the Lake Mývatn area; but, whatever you do, don’t miss out on this extraordinary place!