Iceland’s second-highest waterfall has a drop of 198 m (650 ft) and is located in the Botnsdalur Valley near Hvalfjörður (Whale Fjord) northeast of Reykjavik. Fed by the deep lake of Hvalvatn, the crystal-clear waters of the Botnsá River flow xx and its spindly cascade flings itself over sheer rock to form a deep, narrow canyon covered in mosses and best seen from the southeast side of the river. There is parking space at the end of the road (leave it at junction 47) and a challenging dirt track leads to a dramatic viewing point in the canyon over rough ground and via a spectacular rock arch. Round-trip hikes to the waterfall at Glymur take around three hours and are often combined with visits to Þingvellir National Park to see the source of Iceland’s geothermal activity as the Eurasian and American tectonic plates grind together as they slowly pull apart.
For many years it was believed that Glymur was the highest waterfall in Iceland but the eruption of Eyjafjallajökull in 2010 caused ice melt and subsequently revealed a higher – but very inaccessible – fall coming off the Vatnajökull glacier, which has a drop of over 200 m (656 ft).
Hvalfjörður/Botnsdal 47, 301 Akranes. Hiking boots are recommended. A 90-minute drive from Reykjavik.