Reykjadalur Thermal River

What to expect

Reykjadalur means “steam valley”, and the name fits. The valley lies in the Hengill geothermal area, in Ölfus just north of the town of Hveragerði. Steam vents, bubbling mud and hot springs line the slopes. Down the middle runs the Reykjadalsá, a stream fed by hot springs higher up and cooled by cold side streams lower down. For part of its length the water sits at bathing temperature, and that stretch is the reason most people make the walk.

There is no pool. You sit in the river itself, on a gravel or mossy bed, in water that is usually only 20 to 30 cm (8 to 12 in) deep. A wooden boardwalk runs along the bank in the bathing area, with simple wooden screens to change behind. They are open at the top and not very private. There are no showers, no lockers, no toilets and no bins.

The temperature changes as you move along the stream. A 2026 trail guide gives about 91 to 95°F33 to 35°C where cold water joins in the lower bathing area, 97 to 104°F36 to 40°C in the middle, and over 104°F40°C higher up toward the springs. If you are cold, move upstream. If it is too hot, move down. Above the marked bathing area the water can scald, so do not go there.

This is not a quiet place in summer. Hveragerði’s tourism office estimates that about 1,000 people a day walk the trail. Expect company.

Getting there

The trailhead is a car park in the valley mouth about 3 km (2 miles) north of central Hveragerði, at the end of the road past the town’s northern edge.

• From Reykjavík: About 50 km (31 miles), around 50 minutes. Take Route 1 east over Hellisheiði. Turn off into Hveragerði, drive through the town heading north toward the mountains, and follow the road to the Reykjadalur car park.
• From Selfoss: About 17 km (11 miles), roughly 20 minutes west on Route 1, then north through Hveragerði.

Parking: The car park charges by the hour. Travel guides list about ISK 200 for the first hour and ISK 250 for each hour after, or about ISK 1,000 for a 5-hour stay. You pay with the Parka or EasyPark apps or by card at the machine on the café wall when you leave, with about 10 minutes’ grace to drive out. Cash is not taken. The toilets at the trailhead are included in the parking fee. A café at the trailhead sells coffee and light food, with shorter hours in winter.

The walk: Hveragerði’s tourism site gives about 3.5 km (2.2 miles) to the bathing area, around an hour uphill for experienced walkers. Other guides measure about 3 km each way with roughly 340 to 380 m (1,100 to 1,250 ft) of climbing, and say the first 30 to 45 minutes are the steepest. The path is wide and well used, but it is a real hill walk: loose gravel, steep sections and, in places, mud. Plan on 3 to 4 hours in total with a soak. Close any farm gates behind you.

Reykjaböð: A new paid spa called Reykjaböð has been built at the trailhead. Travel guides list it as opening in September 2026, with passes from ISK 8,900. It has its own guest parking. It is separate from the free river.

When to go

Summer (June to August): The trail is dry and easy, and daylight lasts almost all night. Midday in July and August is the busiest time by far. Start before 9:00 or after 18:00 to share the river with fewer people.

Spring and autumn: Quieter, but often muddy, especially during the spring thaw when the ground is saturated. Visit South Iceland says the trail can be closed, and it asks walkers to keep to the paths to protect the vegetation. Check safetravel.is before you go.

Winter (November to March): Snow and ice cover the trail, so traction spikes, warm layers and a headlamp are close to essential. Add 30 to 60 minutes to your time. High wind and heavy snow can block the access road, and the landowner may close the car park during severe weather warnings. Getting out of warm water into a winter wind is the hardest part. Do not bathe alone in winter, and turn back if the forecast shows wind over 20 m/s.

Rules and etiquette

• Stay on the marked trail and boardwalk. The ground around the vents can be a thin crust over boiling water, and the vegetation is easily damaged.
• Swimsuits on. It is a public, busy place.
• No soap. There are no showers here, so the Icelandic shower-before-bathing rule cannot apply. Just keep soap, shampoo and sunscreen out of the river.
• Carry everything out, including wet swimsuits and towels. There are no bins in the valley.
• No camping, fires or drones in the valley, according to trail guides.
• Dogs on a leash, and not in the river.

Where to stay nearby

• Reykjadalur trailhead: There is guesthouse accommodation at the trailhead, next to the café.
• Hveragerði: About 3 km (2 miles) away, a small town with hotels, guesthouses, a campsite, a geothermal swimming pool, a supermarket and restaurants.
• Selfoss: About 17 km (11 miles) east, the main town of South Iceland, with a wide choice of hotels.
• Reykjavík: About 50 minutes away, so many people visit as a day trip.

Safety notes

• Scalding ground and water: Stay on the path. Do not touch standing water, mud pots or steam vents, and test the river with your hand before you sit down.
• Untested water: The river is not a managed bathing site. Do not drink it, and keep your head above the water.
• Children: The river is shallow, but the ground beside the trail is dangerous. Keep children close and on the path the whole time.
• Weather: Conditions on Hengill change fast. Check the forecast and safetravel.is, carry a charged phone and layers, and turn back if the weather turns.
• Footing: The descent is where people slip, especially on ice or wet gravel.

Nearby stops worth adding

Above the bathing area, the trail continues to Klambragil, a gorge that Hveragerði’s tourism office says nobody who walks this far should skip. A 3.8 km (2.4 mile) loop leads from there up Ölkelduhnjúkur and back into the valley. In Hveragerði, the geothermal park in the middle of town shows off the steaming ground up close. For a soak with less walking, Hrunalaug is about an hour east, near Flúðir.