F578 Arnarvatnsvegur: Into West Iceland's Interior

The F578 Arnarvatnsvegur cuts a lonely path through some of West Iceland's most austere highland terrain, connecting the Borgarfjörður region to the remote interior lakes and volcanic landscapes that define this forgotten corner of the island. This 47-kilometre mountain track offers intrepid drivers access to pristine wilderness areas that see fewer visitors in an entire season than the Golden Circle receives in a single afternoon.

The Route Overview

Beginning at its junction with Route 518 near Húsafell, the F578 initially follows relatively gentle terrain before ascending into the barren highlands that characterise Iceland's interior. The road terminates at Arnarvatn, a substantial lake system nestled beneath the Eiríksjökull glacier, though several challenging side tracks extend the adventure for those equipped with suitable vehicles.

The journey demands a robust 4WD vehicle with high clearance. River crossings, loose volcanic scree, and steep gradients make this route unsuitable for standard rental cars. Budget 3-4 hours for the complete journey to Arnarvatn, though photography stops and exploration will easily extend this to a full day.

Into the Highlands

The Ascent from Húsafell

The first 12 kilometres from the Route 518 junction follow the Hvítá river valley, passing scattered sheep farms and summer houses before the landscape begins its dramatic transformation. Here, the road surface deteriorates from gravel to rough highland track, and the birch scrubland gives way to the stark beauty of Iceland's volcanic highlands.

At kilometre 15, the route crosses the first significant river ford—typically 30-40 centimetres deep during summer months but potentially impassable during spring melt or after heavy rainfall. The water is crystal clear, flowing over black volcanic sand that creates an otherworldly contrast against the surrounding rust-red scoria fields.

The Volcanic Landscape

Beyond the river crossing, the F578 enters a moonscape of ancient lava flows and volcanic debris. This terrain was shaped by eruptions from the Eiríksjökull volcanic system over millennia, creating a palette of colours rarely seen elsewhere in Iceland. Rust-orange oxidised iron deposits streak through black basalt formations, while patches of yellow and green moss cling to the most sheltered crevices.

The road winds through this lunar terrain for 18 kilometres, climbing steadily towards the 650-metre plateau that surrounds Arnarvatn. Visibility can be excellent on clear days, offering views north towards the Langjökull ice cap and south to the distinctive profile of Ok volcano—the first Icelandic glacier officially declared "dead" due to climate change.

Arnarvatn: The Eagle Lake

The Lake System

Arnarvatn itself comprises three connected lakes covering approximately 15 square kilometres, fed by glacial melt from Eiríksjökull and numerous highland springs. The name translates as "Eagle Lake," though golden eagles are now rare visitors to this remote corner of Iceland. The lakes reach depths of up to 84 metres, and their waters remain near-freezing even during the height of summer.

The largest lake, Arnarvatn Stóra, stretches 4.8 kilometres from east to west and provides excellent Arctic char fishing for those holding valid permits. Fishing licences can be purchased online through the Icelandic Angling Association for 8,500 ISK (approximately £50/€60/USD $65) per day, though the remote location means you'll likely have the entire lake to yourself.

Geological Significance

The Arnarvatn area sits within a fascinating geological transition zone where the Eiríksjökull volcanic system meets the older Tertiary basalt formations of West Iceland. This creates unusual mineral compositions in the surrounding rocks, including zeolite deposits that create striking blue and green colourations in certain light conditions.

The glacial lake system itself formed during the last ice age when advancing glaciers carved deep basins in the existing volcanic rock. As the ice retreated approximately 10,000 years ago, these basins filled with meltwater, creating the pristine lake system visible today.

Practical Considerations

Vehicle Requirements

The F578 demands a capable 4WD vehicle with high ground clearance—minimum 200mm. River crossings require careful assessment, and drivers should carry recovery equipment including tow straps and a shovel. Mobile phone coverage is non-existent beyond kilometre 20, making satellite communication devices advisable for solo travellers.

Weather and Timing

The track typically opens between late June and early September, depending on snowfall and spring conditions. Even during summer, weather can change rapidly, with temperatures dropping below freezing at night. Highland winds frequently exceed 60 km/h, and visibility can deteriorate quickly in fog or precipitation.

Check road conditions at road.is before departure, and inform someone of your intended route and return time. The Icelandic Association for Search and Rescue (ICE-SAR) responds to numerous highland emergencies each season, many involving inadequate preparation or unsuitable vehicles.

Fuel and Supplies

No services exist along the F578 or at Arnarvatn. Ensure full fuel tanks before departure—the complete return journey from Húsafell consumes approximately 40-50 litres depending on vehicle type and driving conditions. Carry emergency food, warm clothing, and camping equipment even for day trips.

The Return Journey

The return journey offers different perspectives on the same dramatic landscape, though many travellers choose to camp at Arnarvatn to experience the profound silence and clarity of the highland night sky. Light pollution is non-existent, making this one of Iceland's premier locations for astronomical observation and aurora photography during the early autumn months.

For those seeking the ultimate highland adventure, the F578 Arnarvatnsvegur delivers an authentic taste of Iceland's untamed interior—a landscape where geological forces remain the dominant influence and human presence feels both privileged and temporary.

Getting around Iceland is easiest by car. Compare rental options and find the best deals on Discover Cars — free cancellation available.

Browse and book tours and activities on GetYourGuide — glacier hikes, whale watching, northern lights tours, Golden Circle day trips and hundreds more. Instant confirmation, free cancellation on most bookings.

Planning your Iceland trip? Don't forget travel insurance — SafetyWing offers flexible Nomad Insurance from $56.28/4 weeks, ideal for Iceland's dramatic terrain and ever-changing conditions. Get covered before you go and explore with confidence.