The waterfall Glymur, with a cascade of 196 m, is the highest waterfall of Iceland.
It is situated at the rear end of the Hvalfjörður. Since the opening of the tunnel under this fjord, most people bypass the area. However, it is a very beautiful part of the country with volcanoes and tree plantations.
The river Botnsá leaves the lake Hvalvatn and after a short distance the water falls down alongside the volcano Hvalfell into a canyon with green moss. The waterfall can be accessed from Botnsá, a small village of summerhouses named after the river. From the Botnsá parking area, one can hike up part of the mountain (350 m) on marked hiking paths. To get a better view of the waterfall it is necessary to see it from the south side of the river Botnsá, however the south side trail is strenuous and potentially hazardous, passing along the edges of steep dropoffs.
It is also possible to reach the base of the falls, but only by wading through the Botnsá. There are strong winds and serious risks of rockfall in the narrow canyon bottom.