Cutting into the northeast’s rocky inland plains, Jökulsárgljúfur National Park – an isolated fragment of the enormous Vatnajökull National Park – encloses a 35km stretch of the Jökulsá á Fjöllum, Iceland’s second-longest river. Originating almost 200km south at Vatnajökull, for much of its journey through the park the river flows through the mighty Jökulsárgljúfur, a canyon which is 120m deep and 500m wide in places, forming several exceptional waterfalls and an endless array of rock formations. There are two key sights: the horseshoe-shaped Ásbyrgi canyon in the north of the park, an hour’s drive from Húsavík; and Dettifoss, Europe’s most powerful waterfall, at the park’s southern boundary near Mývatn. In between, the silt-laden river cuts its way between stark grey gorge walls, all set against an unusually fertile backdrop: over half of the country’s native plant species are found here, and in summer the heathland above the gorge is lush and splashed pink and white with flowers.
Ásbyrgi and Dettifoss are connected by hiking trails and two roads either side of the gorge: westerly Route 862, which is rough gravel except for the final 24km stretch between Dettifoss and the Ringroad (there’s long been talk of surfacing the entire thing); and easterly Route 864, which is gravel the whole way. Note that both roads are closed through winter.