Seljavogur

The two tectonic plates are slowly pulling apart at roughly two centimetres a year, and Iceland sits right where the Mid-Atlantic Ridge rises above the sea. The visible fissures across Reykjanes are evidence of that movement. The bridge, completed in the early 2000s, was built as a symbolic link, and it honours the explorer Leifur Eiríksson.

The lagoon was formed by outflow from the nearby Svartsengi geothermal power plant, which uses superheated water drawn from deep below the lava field. Its colour comes from dissolved silica and algae. People soon discovered that bathing in the water seemed to help skin conditions, and a spa grew up around it. The water is renewed regularly.

Gunnuhver is a windswept geothermal field on the Reykjanes peninsula, where plumes of steam rise from vents and a large mud pool bubbles and churns. The ground is stained in shades of ochre, yellow and red, and boardwalks lead you safely through the clouds of steam.