The Ríkishringur circle in Heiðmörk

The Ríkishringur is one of the best-known and most popular trail runs in the Reykjavík greater area, running through the heart of the Heiðmörk nature reserve, which is managed by the Reykjavík Forestry Society. The name arose in a running group around 2009–2010 and has stuck. The route is about 12 km and is made up of several of the area's marked sub-loops, including Vatnahringur, Strípshringur, Skógarhringur and Norðmannahringur. The loop itself is not separately waymarked, so it is wise to study a map of Heiðmörk before a first attempt or to go with someone who knows the route. Running clockwise and generally bearing left is recommended. Elevation gain is moderate, around 160 metres over the whole route, but the surface is soft forest and gravel paths, making it a good strength and endurance loop. Heiðmörk is green and sheltered and therefore ideal in windy weather. On summer days expect considerable traffic on the paths, both walkers and cyclists, so runners and cyclists should take mutual care. There is parking at Helluvatn and elsewhere in Heiðmörk. The area is a nature reserve, so treat the environment with care.