Reykjadalur Hot River: Hike to a Geothermal River in South Iceland

A geothermally heated river in a steaming valley near Hveragerði — hike 3 km to find your perfect bathing temperature.

Updated February 1, 2026By the Iceland.org Travel Team
Location
Hveragerði
South Iceland • Free admission
Reykjadalur, meaning "Steam Valley," is one of Iceland's most rewarding free natural bathing experiences. Located just outside Hveragerði, a 45-minute drive from Reykjavík, the trail winds through a geothermal landscape of bubbling mud pots, steaming vents, and lush green hillsides before reaching the warm river. Wooden boardwalks along the riverbank let you choose your ideal temperature — cooler downstream, hotter upstream.
Safety + sourcing
Last updated: 2026-02-01

Stay on marked trails in geothermal areas. The river is free to access but there are no lifeguards or facilities.

Sources to check
Hike
3 km each way

Well-marked trail from Hveragerði parking

Temperature
Varies 20–50°C

Find your perfect spot along the river

Cost
Free

No admission fee or booking required

What to Expect

River Bathing (20-50°C)

Soak in a naturally heated river where temperatures range from 20°C downstream to over 50°C near the geothermal source upstream. Find your ideal 38-40°C spot

Scenic 3 km Valley Hike

Well-marked trail with 150 m elevation gain passes bubbling mud pots, hissing steam vents, and a small waterfall. Takes 45-60 minutes each way

Free Admission

No entrance fee or booking required. The experience is entirely free -- one of Iceland's best free natural attractions

What to Bring

Swimsuit (wear under clothes), towel, sturdy hiking shoes, water bottle, and snacks. Water shoes helpful for the rocky riverbed. No facilities at the river

Wooden Privacy Screens

Small wooden privacy screens along the riverbank serve as basic changing areas. No permanent changing rooms, toilets, or showers at the bathing spot

45 Minutes From Reykjavík

One of the closest natural hot spring experiences to the capital. Easy half-day trip from Reykjavík, combinable with Hveragerði town exploration

Getting There

From Reykjavík, drive 45 km south on Route 1 to Hveragerði (about 45 minutes). In Hveragerði, follow signs to the Reykjadalur trailhead -- the parking lot is at the end of a short road on the upper edge of town. The parking area has restroom facilities and an information board. It can fill up quickly on summer weekends, so arrive before 10 AM. The 3 km trail takes 45-60 minutes each way with 150 m elevation gain on a well-marked path. No 4WD required to reach the parking area. The nearest services (cafes, shops, fuel) are in Hveragerði town center (5 minutes by car).

Best Time to Visit

June through August: ideal conditions with dry trails, long daylight (up to 21 hours), and warmest air temperatures. This is also peak crowd season -- arrive before 9 AM or after 5 PM for fewer people. September through October: autumn colors in the valley, thinner crowds, and cooler air that enhances the contrast of warm river bathing. November through March: winter hiking is possible but requires microspikes or crampons, warm waterproof layers, and a headlamp. The experience of soaking in warm water with steam rising against cold air and potential northern lights is unforgettable. April through May: trails drying out with returning daylight and moderate crowds. Weekday mornings are quietest in every season.

Planning help

Reykjadalur FAQs

Quick answers with safety notes where it matters.