There are some rock stacks on the beach that can only be briefly glimpsed from further down the main road. You are unlikely to even spot them unless you know they are there. They seem to be the remains of a vein of rock that has been exposed as the softer surrounding rock weathered away. If you go past the rocks you need to watch the tide, as it comes in rapidly and you could get shut in by the tide.
This is a lovely stop on the road around Hvalfjörður. Hvalfjarðareyri (English: Whale Fjord Spit) is common land and as such open to all. There is a small automated lighthouse at the end of the spit, and along the western shore of the spit you can sometimes find spherulites, small, purplish round rocks, often stuck together in clusters. Most are under 2 cm in diameter and while they don’t possess the showy beauty of crystals, they still make for cool souvenirs, especially the clustered ones. It’s a nice hike from the end of the road to the lighthouse and back.