Iceland — Akureyri
Iceland's Askja Caldera Trail: a 60km, 2-3 day, challenging trek through the raw volcanic highlands. This remote route traverses an otherworldly landscape, a vast desert of ancient lava fields and stark craters, famously used for lunar training. Expect rugged terrain and profound wilderness on this unique Icelandic adventure.
Distance: 60.0 km
Elevation Gain: 800 m
Difficulty: Challenging
Duration: 2-3 days
The Askja Caldera Trail is one of the most profound wilderness experiences in the northern hemisphere—a 60-kilometre trek through the raw, volcanic soul of the Icelandic Highlands. Located within the Dyngjufjöll mountains on the northern edge of the Vatnajökull National Park, this route traverses a landscape so otherworldly that it was famously used by NASA to train Apollo astronauts for lunar landings. This is not a trail of lush forests or rolling meadows; it is a journey through vast deserts of black tephra, jagged obsidian lava fields, and towering rhyolite peaks that shimmer with ethereal colours under the midnight sun. The centrepiece of the trek is the massive Askja caldera itself, a 45-square-kilometre collapse feature containing the sapphire-blue Lake Öskjuvatn and the milky-teal, geothermal Viti crater.
Accessing the Askja region is an adventure in its own right, requiring a high-clearance 4x4 vehicle and the negotiation of unbridged glacial rivers. The trail typically begins at the Draumakofa hut or the Dreki mountain station, weaving through the heart of the Odadahraun—the "Desert of Misdeeds"—Iceland’s largest lava field. This is a place of absolute silence, where the scale of the geology humbles the human spirit and the weather can shift from sun-drenched stillness to a blinding sandstorm in minutes. For those seeking a true escape from the modern world, the Askja Caldera Trail offers a stark, minimalist beauty that is unmatched anywhere else on Earth.
The Askja Caldera Trail is a masterclass in volcanic geology and high-altitude desert trekking. Unlike the popular Laugavegur trail to the south, Askja remains relatively uncrowded, offering a sense of isolation that is increasingly rare in Iceland. The route is defined by the Dyngjufjöll massif, a cluster of mountains that rose through the ice during the last glacial period. The caldera at its heart is a nested system of three subsidences, the most recent of which was formed during a cataclysmic eruption in 1875. Walking here is a sensory experience: the crunch of pumice underfoot, the smell of sulphur wafting from geothermal vents, and the sight of the vast, empty horizon of the interior highlands.
The trek is physically demanding, not necessarily because of extreme elevation gain—the total ascent is a manageable 800 metres—but because of the terrain. Hikers must navigate through "Aa" lava (sharp, jagged blocks) and "Pahoehoe" lava (smooth, ropey flows), as well as deep fields of volcanic ash that can make every step feel like walking through heavy sand. Water is a critical logistical challenge; the porous volcanic soil swallows rainfall instantly, meaning there are long stretches with no surface water. Success on this trail requires meticulous planning, a robust physical constitution, and a deep respect for the unpredictable nature of the Icelandic interior.
The visual rewards, however, are staggering. Standing on the rim of the Askja caldera, looking down at the 220-metre-deep Lake Öskjuvatn—the second deepest lake in Iceland—is a moment of profound awe. Beside it, the smaller Viti crater (meaning "Hell") offers the surreal opportunity to swim in geothermal waters surrounded by a frozen landscape of snow and ash. The light in the highlands is legendary; during the peak of summer, the sun barely dips below the horizon, casting long, golden shadows across the black sands and turning the rhyolite mountains into glowing beacons of ochre and violet.
The history of Askja is a saga of geological violence and human exploration. For centuries, the region was part of the "Odadahraun," a vast, trackless lava desert that was feared by Icelanders. Folklore suggested it was the haunt of outlaws and evil spirits, a place where no God-fearing person would venture. It remained largely unexplored until the late 19th century. The event that changed everything was the massive explosive eruption of 1875. This eruption was so powerful that its ash reached as far as Norway and Sweden, and it devastated the farming communities of East Iceland, triggering a wave of emigration to North America. The eruption caused the roof of the central magma chamber to collapse, creating the caldera and the depression that eventually filled with water to become Lake Öskjuvatn.
In 1907, the region became the site of a haunting mystery. Two German scientists, Walter von Knebel and Max Rudloff, arrived to study the caldera. While exploring Lake Öskjuvatn in a small boat, they vanished without a trace. Von Knebel’s fiancée, Ina von Grumbkow, led an expedition the following year to find them, but no remains were ever discovered. Today, a small memorial plaque stands near the lake, a somber reminder of the dangers inherent in this volatile landscape. The mystery of their disappearance continues to fascinate historians and geologists alike.
In the 1960s, Askja gained international fame for a different reason. NASA geologists identified the area as the most moon-like terrain on Earth. In 1965 and 1967, groups of Apollo astronauts, including Neil Armstrong and Buzz Aldrin, were sent to the Askja region to practice geological sampling and to familiarise themselves with the challenges of navigating a barren, volcanic environment. The astronauts stayed in the Dreki huts and spent their days exploring the lava fields, a history that adds a layer of cosmic significance to every step a modern hiker takes on the trail. The local community in Akureyri and the nearby Husavik still celebrate this connection through the Exploration Museum.
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The window for hiking the Askja Caldera Trail is exceptionally narrow. Because the trail is located in the high interior, the access roads (F-roads) are closed by snow for most of the year. Typically, the roads F88 and F910 do not open until late June or early July, and they often close again by early September. Even during the peak of summer, the weather in the highlands is notoriously fickle. It is not uncommon to experience a snowstorm in the middle of July, followed by temperatures of 20 degrees Celsius the next day.
Summer (July to August): This is the only viable time for the trek. The days are characterised by 24-hour daylight, which provides a safety margin for navigation but can disrupt sleep patterns. The primary weather hazards during this time are high winds and sandstorms. When the wind picks up across the Odadahraun, it carries fine volcanic dust that can reduce visibility to a few metres and scour exposed skin. Rain is frequent, often coming in horizontal sheets, and the temperature at night regularly drops toward freezing.
Shoulder Season (Late June and Early September): Attempting the trail during these windows is a gamble. In late June, large snow patches often cover the trail, making navigation difficult and increasing the risk of falling through snow bridges over hidden lava fissures. In September, the days shorten rapidly, and the first major autumn storms can bring heavy snow and sub-zero temperatures, potentially stranding hikers and vehicles. There are no services in the area outside of the peak summer months, and the wardens at Dreki depart once the roads are officially closed.
Winter (October to May): The Askja region is strictly off-limits to all but the most experienced polar explorers during winter. The area is buried under metres of snow, and the winds can reach hurricane force. Access is only possible via modified "Super Jeeps" or on skis, and the risk of extreme hypothermia and getting lost is absolute. For the recreational hiker, winter is a time to stay away and plan for the following summer.
Day 1: Draumakofa Hut to Dreki Mountain Station
Day 2: Dreki to Askja Caldera and Viti Crater (Loop)
Day 3: Dreki to Dyngjufell Hut
Important Notes:
Planning a trip to Askja is significantly more complex than a standard European hike. The primary hurdle is logistics. You must have a 4x4 vehicle to reach the trailhead. Standard rental cars are strictly prohibited on F-roads, and attempting to drive one here will void your insurance and likely result in a stranded vehicle and a very expensive rescue fee. The most common base for the trip is Akureyri, the "Capital of the North," which has all the necessary services, including supermarkets, outdoor gear shops, and car rental agencies specialising in highland vehicles.
Fitness requirements are moderate to high. While the elevation gain isn't extreme, the uneven and soft terrain is taxing on the ankles and knees. You should be comfortable walking 20+ kilometres a day with a full pack. Furthermore, you must be self-sufficient in navigation. There are no signposts with distances, and in a sandstorm, you will lose all visual landmarks. Familiarise yourself with your GPS device and carry spare batteries.
Accommodation in the Askja region is managed primarily by the Akureyri Touring Club (Ferðafélag Akureyrar - FFA). There are three main options for hikers on this route.
Dreki Huts: The main hub. There are two large huts that can accommodate about 60 people in total. They feature bunk beds with mattresses, a shared kitchen with gas stoves, and a separate building with toilets and showers (showers require a small fee). During the summer, wardens are stationed here to provide information and manage bookings.
Draumakofa and Dyngjufell Huts: These are much smaller and more basic "emergency" style huts. They provide shelter and bunks but have very limited facilities. You should not rely on finding space here without prior coordination, and you must bring your own cooking equipment.
Camping: There is a designated campsite at Dreki. Camping is only allowed in designated areas to protect the fragile volcanic soil. The ground is hard and rocky, so sturdy tent pegs are essential. There is no shade or wind protection, so your tent must be high-quality and capable of withstanding gale-force winds.
Booking Requirements: Hut spaces sell out months in advance. You can book through the FFA website. Camping does not usually require a pre-booking but you must register with the warden upon arrival. Costs for huts are approximately 10,000 to 12,000 ISK per night, while camping is around 2,500 ISK per person.
Currently, no formal "permit" is required to hike the Askja Caldera Trail. However, the region is part of the Vatnajökull National Park, and there are strict regulations that all visitors must follow. The most important requirement is registration. All hikers are strongly encouraged to register their travel plans on Safetravel.is, the official Icelandic safety portal. This ensures that search and rescue teams know your intended route and expected return time.
National Park Regulations:
Warden Interaction: Upon arriving at Dreki, you must check in with the park wardens. They provide essential updates on the "F-road" conditions and the safety of the Viti crater. Occasionally, the crater is closed to swimming due to high levels of CO2 or unstable slopes. Following their instructions is mandatory for your safety and the preservation of the site.
Detailed route notes, maps, logistics & tips for the Askja Caldera Trail (PDF).
Precisely traced GPX for the Askja Caldera Trail, ready for your GPS or favourite mapping app.
The journey to Askja takes you through some of Iceland's most spectacular northern landscapes. Consider these additions to your itinerary:
The "Highland Reality": Safety in the Icelandic Highlands is a matter of self-reliance. There is no mobile phone coverage in most of the Askja region. If you get into trouble, you cannot simply call for help. Carrying a Personal Locator Beacon (PLB) or a satellite communication device (like a Garmin inReach) is not just recommended—it is essential.
Weather Hazards: The greatest threat is hypothermia. Because the air is dry and often windy, sweat evaporates quickly, chilling the body. If you get wet from rain or a river crossing and the wind picks up, your core temperature can drop dangerously fast. Always wear synthetic or wool layers; never wear cotton, which loses all insulating properties when wet. Sandstorms are another unique hazard. If caught in one, seek shelter behind a large rock, cover your face, and wait it out. Do not attempt to navigate in zero visibility.
Volcanic Gas: Askja is an active volcanic system. While it is currently quiet, there are areas where volcanic gases (particularly CO2 and H2S) can accumulate in low-lying depressions or inside the Viti crater. These gases are often odourless and can be fatal. If you feel lightheaded or notice a "rotten egg" smell, move to higher ground immediately. Always follow the wardens' advice regarding the safety of the crater.
River Crossings: If you are driving to the trailhead, you will likely encounter river crossings on the F88 or F910. These rivers are glacial and their depth can change throughout the day. They are usually lowest in the early morning and highest in the late afternoon as the sun melts the glaciers. Never cross a river alone, and if you are unsure of the depth, wade in on foot (with a safety line) to test it before driving your vehicle across.
Emergency Services: The Icelandic Search and Rescue (ICE-SAR) is a volunteer organisation. While they are world-class, a rescue in the highlands can take many hours or even days depending on the weather. Your primary goal should be to avoid needing them through conservative decision-making.
Drekagil (Dragon Ravine): Located right next to the Dreki huts, this canyon is a geological marvel. The walls are composed of dark, twisted basalt that resembles the scales and wings of dragons. A short hike up the ravine leads to a hidden waterfall. It is a perfect evening walk after arriving at the station.
Mount Herðubreið: While not part of the main Askja trail, this tuya (table mountain) dominates the northern horizon. It is often called the most beautiful mountain in Iceland. Climbing it is a serious undertaking involving steep scree and rockfall risk, but for experienced mountaineers, it is the ultimate highland prize.
The NASA Training Sites: Ask the wardens at Dreki for the approximate locations where the Apollo astronauts practiced. Walking in the footsteps of Neil Armstrong adds a layer of historical awe to the landscape. You can still find areas that look exactly like the photographs taken during the 1960s training missions.
Öskjuvatn Shoreline: Most people view the lake from the rim, but it is possible to walk down to the water's edge. The scale of the caldera walls rising 300–500 metres above the water is best appreciated from below. The water is crystal clear and freezing cold, reflecting the sky with startling intensity.
The Icelandic Highlands are one of the last great wilderness areas in Europe, but they are incredibly fragile. The growing number of tourists has put immense pressure on this delicate ecosystem. Because of the cold climate, the growing season is very short, and damage to the soil or vegetation can take centuries to heal.
Core Principles for Askja:
