Glymur is the second highest waterfall in Iceland at 198 metres (660 feet), and drops into a deep, narrow canyon. It is located in Botnsdalur Valley in the river Botnsá in Hvalfjörður. From Reykjavík just before entering the tunnel under fjord Hvalfjörður take the road 47, and then a 3 km gravel road to a car park. From the car park there is a hiking trail to Glymur. Following the marked trail towards Glymur, there are two trail options ,a trail that leads to the north side or south side of Glymur. The south side trail gives a better view of Glymur. The trail to Glymur is about 2.5 km long, so the hiking to and fro is about 5 km. Do note that part of the trail can be quite a steep climb and you will be crossing one river on a wooden pole. it can be said that this trail is sometimes a challenging hike, and not for people daunted by heights.
GPS 64.390837, -21.252282
Car park GPS 64.385135, -21.293374