Ásbyrgi in Norðurþing

You're standing in Ásbyrgi, a canyon in the north of Iceland, about 38 kilometres east of Húsavík. Take a look around. The rock walls curve together into a giant horseshoe, and they rise as high as a hundred metres. The canyon is roughly three and a half kilometres long and more than a kilometre wide. It's part of Vatnajökull National Park.