10 hardest long-distance treks in Europe

1. Laugavegur + Fimmvörðuháls

Location: Iceland
Duration: 3-5 days
Distance: 55km
Difficulty factors: challenging terrain, volatile weather, challenging navigation

The Laugavegur Trail is Iceland’s most iconic trek and only gets better (and tougher) when it’s paired with the Fimmvörðuháls extension over a volcanic pass. While relatively short, the trail is deceptively challenging. Hikers traverse a surreal and often brutal landscape of geothermal hot springs, glacial rivers, black sand deserts and jagged lava fields. The terrain is rough and varied, requiring constant attention: soft ash, scree slopes, and river fords slow progress and test balance and endurance.

The addition of Fimmvörðuháls raises the stakes dramatically, sending trekkers over a high volcanic pass between two glaciers. The weather here is extremely unpredictable, with high winds, sudden snow and driving rain possible even in summer.

Several sections are remote, with limited shelter between mountain huts, meaning self-sufficiency and solid navigation skills are essential. Despite its short distance, the combination of exposed terrain, volatile weather, river crossings, and continuous physical demand makes this Icelandic adventure one of the hardest long-distance treks in Europe.

2. Skye Trail 

Location: Scotland, UK
Duration: 6-8 days
Distance: 128km
Difficulty factors: unmarked trails, changeable weather, challenging navigation

The Isle of Skye holds a special place in many people’s hearts – mine included. Its romantic history, sculpted mountains and wild coastline draw visitors from all around the world. The best way to explore the island is slowly via the challenging. Skye Trail

Currently unmarked and only for experienced backpackers and backpackers, this challenging trek provides hikers with a tour of Skye’s most iconic landforms – including the Trotternish ridge and the Cuillin ridge – as well as of its turbulent history, from the Iron Age forts to the ruins of the Clearance villages.

Whether making use of island hospitality or opting for the freedom of a tent, completing the continuous route represents a real challenge and a fitting match for the epic landscapes found on Skye.

3. Haute Route 

Location: France and Switzerland
Duration: 10-14 days
Distance: 180km
Difficulty factors: steep daily ascents and descents, high-altitude passes, snow and ice, unpredictable weather

Linking Chamonix in France to Zermatt in Switzerland, the legendary Haute Route is often described as the ultimate Alpine trek. The trail takes hikers beneath some of Europe’s highest peaks, including Mont Blanc and the Matterhorn, with constant views of glaciers, jagged ridgelines and snow-capped giants.

But this beauty comes at a price: the route involves a cumulative ascent of more than 12,000m, with daily climbs and descents that can really test a trekker’s stamina. Even in high summer, snowfields linger on the high passes, demanding sure-footedness and sometimes an ice axe or crampons.

Trekkers must cross 10 major mountain passes, often at elevations above 2,900m, where thin air and sudden storms pose real threats. The result is one of the most dramatic journeys in the Alps, culminating in a jaw-dropping approach to Zermatt with the Matterhorn rising ahead.

4. Peaks of the Balkans

Location: Albania, Kosovo and Montenegro
Duration: 10-14 days
Distance: 182km
Difficulty factors: steep ascents and descents, rocky terrain, scrambling required, multiple border crossings require permits, changeable weather

The Peaks of the Balkans Trail is a relatively recently developed cross-border long-distance route through the spectacularly wild and rugged borderlands of Montenegro, Albania and Kosovo. The route winds through the Accursed Mountains (Prokletije), one of Europe’s most rugged ranges, across trails that are rocky, uneven and can involve scrambling or traversing scree slopes.

The circular route takes in remote valleys, lakes and alpine passes, travelling through tiny mountain villages that can feel like forgotten. It’s a corner of Europe few people are familiar with, let alone visit.

5. GR20

Location: Corsica, France
Distance: 180km
Duration: 14-16 days
Difficulty factors: rocky terrain, scrambling required, high temperatures, thunderstorms, early starts, long days

I just returned from trekking the GR20 and, while it is often referred to as Europe’s toughest trek, I’m not convinced that moniker is entirely justified. That said, even though it may not be the longest, highest or most remote, the terrain is what really stands the GR20 apart. Geologically speaking, the mountains of Corsica are the far southwestern tip of the mainland European Alps – hence the island’s nickname, ‘mountain in the sea’.

The result is terrifically hard granite underfoot, which rarely produces more than a few meters of flat path. Hikers tackle relentless ascents and descents that seem to go straight up or down, crossing knife-edge ridges, scrambling over boulder fields and navigating sections where steel cables and chains are bolted to the rock.

Unlike mainland mountain routes, there are few gentle valleys to be found along the GR20 – just plunging gorges, wind-scoured plateaus and high passes where snow can linger even into summer. There are regularly challenging scrambles – technically and physically – throughout the route. During our trek, there was at least one scramble to overcome every day.

6. Kungsleden

Location: Sweden
Duration: 21-28 days
Distance: 440km
Difficulty factors: changeable weather, mosquitoes, boat crossings, long distances between huts

Sweden is home to one of Europe’s last wildernesses: Lapland. And within it is one of Europe’s finest long-distance hiking trails, the Kungsleden (King’s Trail) through Sarek National Park. You need to be the adventurous type just to make it out here, as there are the trails are irregularly marked and huts, despite being well-maintained, can be few and far between, particularly in the southern section of the trail.

Expect three to four weeks of long trail days, unpredictable weather and swarms of mosquitoes in summer. Several lake and river crossings require rowboats or local ferries, and in the southern sections, hikers face 30-kilometre stretches without huts or services.

While less wild than Norway’s Nordkalottruta or Greenland’s Arctic Circle Trail, the Kungsleden still demands stamina, resilience and self-sufficiency across its remote Arctic landscapes of tundra, glaciers and birch forests.

7. Arctic Circle Trail

Location: Greenland (Denmark)
Duration: 7-10 days
Distance: 165km
Difficulty factors: remote location, limited support, unmarked trails, unpredictable weather

Geographically in North America, but politically in Europe, as Greenland is an autonomous territory within the Kingdom of Denmark, the ACT deserves a place on this list.

I trekked the Arctic Circle Trail back in 2019, but fell tantalisingly short of the finish as a freak wildfire swept across the tundra. Regardless, the region is profoundly beautiful, while the trail is wild and challenging. As such, I have vowed to return one day.

The major challenges include carrying a heavy pack for long periods filled with all the food and supplies required for at least seven days in the backcountry. Additionally, the sheer remoteness of the trail means trekkers must carry everything they need to deal with any eventuality, knowing that there is little chance of outside support unless it’s an emergency.

Trekkers should plan for every type of weather, including strong winds, sleet and snow, heavy rain and sub-freezing temperatures. I trekked the Arctic Circle Trail during a summer of unprecedented temperatures in the Arctic, which had caused widespread wildfires throughout the polar region. That said, I spent two weeks in Greenland and didn’t see rain until the day I departed. As I said, plan for every eventuality.

8. Haute Randonnée Pyrénéenne (HRP)

Location: Andorra, France and Spain
Duration: 30-50 days
Distance: 800km
Difficulty factors: long overall and daily distances, steep ascents and descents, unmarked trails, unpredictable weather, high-altitude mountain passes, snowfields

The HRP is considered the wildest of the Pyrenean crossings, following hundreds of kilometres of high-altitude trails that weave between France, Spain and Andorra. Unlike the GR10 or GR11, the HRP is often unmarked, demanding advanced navigation skills over rugged terrain and high mountain passes, frequently above 2,500m.

Snowfields can linger into summer, and some exposed sections require careful footing, making it a serious test of stamina and competence. Trekkers must also contend with steep ascents and descents, remote stretches far from villages or refuges, and the unpredictability of Pyrenean weather, which can shift from sunshine to storms in minutes.

9. Nordkalottruta

Location: Norway, Sweden and Finland
Duration: 40-55 days
Distance: 800km
Difficulty factors: long overall and daily distances, remote location, limited support, unforgiving terrain, unmarked trails, unpredictable weather

The Nordkalottruta (The Arctic Trail) ticks every tough box. It is considered an extremely challenging trek for several reasons, many of which combine to make it an outrageously formidable adventure for even the most experienced hikers.

For starters, the trail stretches over 800km across the borderlands of Norway, Sweden and Finland – some of the most remote wilderness in all of Europe – and shares a section with the Kungsleden. Several sections boast long distances between huts or settlements, meaning trekkers must carry enough supplies for days at a time.

Located entirely above the Arctic Circle, the trail has extremely unpredictable weather such as sudden snow, heavy rain, strong winds and extreme cold, even in summer. Throw in the navigation challenges of following unmarked trails over demanding terrain that includes bogs, river crossings, mountains, tundra and forests, and you probably have the hardest long-distance trek in Europe.

10. GR11 (Trans-Pyrenean Trail)

Location: Spain
Duration: 45-60 days
Distance: 840km
Difficulty factors: long overall and daily distances, steep ascents and descents, lack of water, extreme heat, unpredictable weather

The GR11 traverses the Spanish Pyrenees from the Atlantic to the Mediterranean, across some of Europe’s most rugged terrain. Daily climbs and descents are relentless, with long stretches that offer limited water and shelter, especially in summer. Hikers face extreme heat in valleys, isolated sections and the cumulative physical strain of continuous mountainous terrain.

Even with trail markings, hikers must be prepared for rapidly changing weather, from intense sun to sudden thunderstorms. The combination of length, elevation gain and logistical challenges makes the GR11 one of the hardest long-distance treks in Europe.