Askja: The Lunar Landscape of Iceland

Deep in the heart of the Icelandic Highlands, where the roads turn to gravel and the vegetation disappears, lies a place that doesn’t feel like Earth. Askja sits hidden inside the Dyngjufjöll mountains: a nested set of calderas so stark and desolate that NASA sent Apollo astronauts here to train for the Moon.

This remote wilderness is defined by two things: the massive, sapphire-blue lake Öskjuvatn (Iceland’s deepest lake) and the small, milky-blue explosion crater Viti (“Hell”), where brave tourists swim in geothermal waters on the edge of an active volcano.

Geological Context: The Northern Volcanic Zone

Askja is the central volcano of a massive volcanic system in the Northern Volcanic Zone.

• The Caldera Complex: “Askja” actually refers to the caldera itself (the word means “box” or “caldera” in Icelandic). The complex was formed by multiple collapses of the magma chamber roof over thousands of years.
• The 1875 Collapse: The main caldera we see today was largely shaped by a catastrophic event in 1875. The ground collapsed, and the depression filled with groundwater, creating Lake Öskjuvatn.

Eruptive History: The Disaster of 1875

For most of Iceland’s history, Askja was unknown, hidden in the inaccessible interior. That changed in 1875.

The Great Ash Fall

In March 1875, a massive Plinian eruption blasted tephra (ash and pumice) high into the atmosphere.

• Impact on Iceland: The wind blew the poisonous ash eastwards, burying the farms in the East Fjords. The devastation was so severe that it triggered a wave of mass emigration. Many Icelanders left their homes forever, moving to “New Iceland” in Canada (Manitoba).
• Reach: The ash cloud traveled as far as Norway and Sweden, confusing Scandinavians who woke up to gray dust on their windows.

The 1961 Eruption

The last eruption occurred in 1961. It was a fissure eruption on the northern rim of the caldera. It was much smaller and more “tourist-friendly” (effusive lava flows) than the explosive 1875 event. The lava field from this eruption, Vikrahraun, is still stark black and devoid of moss.

The NASA Connection: Training for the Moon

In the 1960s, NASA was preparing for the Apollo missions. They needed a place on Earth that resembled the geology of the Moon—barren, volcanic, and geologically young. They chose Askja.

• The Astronauts: Neil Armstrong and Buzz Aldrin walked these lava fields before they walked on the Moon. They studied the geology to learn how to identify different types of rocks.
• The Legacy: Today, a monument stands in the highlands commemorating this connection. When you look around the gray, rocky expanse of Askja, it is easy to see why NASA chose it. It is an alien world.

Hazards: The Sleepy Dragon

Askja has been quiet since 1961, but it is not dead.

• Unrest (2023-2024): In recent years, the land around Askja has been rising (inflating) at a rapid rate—over 70cm in two years. This indicates that magma is accumulating at a shallow depth (2-3 km).
• The Lake: In winter 2023, the ice on Lake Öskjuvatn melted unexpectedly, likely due to increased geothermal heat from the bottom.
• Status: The volcano is currently on “Yellow” alert. A new eruption could happen with little warning, potentially explosive due to the interaction with the lake water.

Tourism: Journey to the Center of Nowhere

Visiting Askja is a serious undertaking. It is located north of the Vatnajökull glacier and is only accessible during the summer months (late June to September).

The Road (F88 / F905 / F910)

There is no paved road. You must take “F-roads” (mountain tracks).

• River Crossings: The route involves crossing unbridged glacial rivers, including the notorious Lindaá. Small SUVs often drown here. You need a proper 4x4 with high clearance (like a Land Rover Defender or modified Toyota Land Cruiser).
• The Desert: You drive for hours through the Ódáðahraun (“Lava of Evil Deeds”), a vast black desert where outlaws used to hide.

The Hike

From the parking lot at Vikraborgir, it is a 2.5 km hike across the black pumice fields to the lake.

• Viti: The reward is Viti. It is a steep-sided explosion crater filled with opaque, teal-blue water. The water is around 25°C (77°F). Hiking down the slippery mud banks to swim is a bucket-list experience, but be careful—the path is steep and the sulfur smell is strong.
• Öskjuvatn: Behind Viti lies the vast Öskjuvatn. It is 220 meters deep. It is cold, ominous, and beautiful.

The Mystery of 1907: Vanished without a Trace

Askja has a dark history. In 1907, two German scientists, Walter von Knebel and Max Rudloff, visited the lake to study it. They took a small boat out onto the water and were never seen again.

• The Search: Von Knebel’s fiancée, Ina von Grumbkow, led an expedition the following year to find them, but no trace was ever found.
• The Theories: Did the boat capsize in sudden bad weather? Were they killed by a sudden release of gas from the lake bottom? Or did a rockslide crush them? The mystery remains unsolved, adding a ghostly aura to the silent blue lake.

The 2014 Holuhraun Connection

Askja does not act alone. In 2014, a massive eruption occurred at Holuhraun, located just north of the Vatnajökull ice cap.

• The Link: Scientists discovered that the magma feeding the Holuhraun eruption actually originated from the Bárðarbunga volcano, but it traveled laterally through the crust, passing dangerously close to the Askja magma chamber.
• Stress Transfer: This event shook the foundations of Askja, and scientists believe the stress changes from 2014 might be one of the reasons Askja is inflating today.

Photography Guide: Capturing the Alien World

Askja is a photographer’s dream, but it challenges your equipment.

• The Viti Shot: The classic shot is looking down into the Viti crater from the rim, with the vast blue Öskjuvatn behind it. A wide-angle lens (16-24mm) is essential to fit both lakes in the frame.
• Weather: Be prepared for dramatic weather. Rainstorms sweeping across the caldera can create incredible rainbows, but also threaten your gear. Bring a rain cover.
• The Black Desert: On the drive in, stop to photograph the Ódáðahraun. The endless black sand against the gray sky creates a minimalist, fine-art aesthetic.

Practical Tips for the Journey

1. Check Road Conditions: Always check road.is before leaving. The mountain rangers close the roads if the rivers are too high.
2. Fuel: There are no gas stations in the highlands. Fill up at Mývatn or Egilsstaðir and carry a spare jerry can if you are unsure of your vehicle’s range.
3. Clothing: Even in July, it can snow at Askja. Dress in layers: wool base layer, fleece, and a waterproof shell. Do not wear jeans.