Reykjadalur Hot Spring River

Reykjadalur, the Steam Valley, lies above the town of Hveragerdi in South Iceland, roughly 45 km and 40-45 minutes by car east of Reykjavik on Route 1. The trailhead is at the edge of Hveragerdi, and the Straeto bus route 51 serves the town, leaving a walk of about 3 km to the start; guided tours from Reykjavik also run here. The return hike is about 7 km with an ascent of around 210 m and usually takes 2.5-3.5 hours, which places it in the moderate category because of the sustained uphill sections rather than technical difficulty. The path follows a clear, well-trodden track, mostly gravel and dirt with some boardwalk sections protecting the fragile ground near geothermal areas. Along the way hikers pass bubbling mud pots, steaming vents and coloured clay slopes, and the landscape is exposed with almost no shade. The route climbs over a ridge, then drops towards the valley where a warm stream, the Reykjadalsa river, flows. A designated bathing stretch is marked with wooden boardwalks and changing screens, where cold water from the main river mixes with hot water from the hillside so that bathers can choose their temperature. Walkers should stay on marked paths because the ground around the vents can be dangerously hot. Water is not safe to drink from the thermal streams, and there are no huts or shelters, so hikers carry their own supplies. The bathing area has simple changing screens but no showers. Swimwear, a towel, a windproof layer and a bag for wet clothes are the usual equipment. Hikers who skip the bath can turn around at the boardwalk viewpoint above the valley. The trail is busiest at midday in summer, and conditions can be slippery in wet weather and icy in colder months. The recommended season runs from May to October.