Þorbjörn Volcanic Ridge Watch

A Tuya Above Grindavík

Þorbjörn is a flat-topped tuya — a volcano built up beneath glacial ice during the last ice age — standing roughly 240 metres over the lava-strewn lowlands beside the fishing town of Grindavík. Its weathered hyaloclastite ridge and the deep cleft of Þjófagjá make it one of the most recognisable landmarks on the entire peninsula.

The Reykjanes Volcanic Zone

The mountain sits squarely on the Reykjanes volcanic system, where the Mid-Atlantic Ridge rises onto land and the North American and Eurasian plates pull apart. After centuries of dormancy, this stretch of the Sundhnúkur crater row reawakened, sending fissures and lava across the surrounding fields and making Þorbjörn a focal point of Icelandic geology.

Why It Is Watched

Just below lie the Svartsengi geothermal plant and the famous Blue Lagoon, so persistent ground uplift and seismicity here are tracked minute by minute. GPS stations and tiltmeters on the slopes feed scientists at the Icelandic Met Office, and this elevated vantage offers a sweeping panorama across the terrain they study.

A Living Landscape

Beyond the immediate volcanic drama, the scene captures the raw, treeless beauty of Reykjanes — green moss spreading over old lava, jagged outcrops, and the broad panoramic sweep toward the surrounding plain. It is a window onto one of Earth's most dynamic and accessible rift landscapes.