Breiðafjörður

Breiðafjörður (lit. widening fjord) is a large shallow bay, about 50 km wide and 125 km long, in the west of Iceland. It separates the region of the Westfjords (Vestfirðir) from the south of the country. Breiðafjörður is encircled by mountains, including the glacier Snæfellsjökull on the Snæfellsnes peninsula to the south and the West Fjord peninsula to the north. An interesting feature of the bay is that the northern tip was formed about 15 million years ago, whereas the southern end at Snæfellsnes was formed less than half that time ago.

Breiðafjörður has a spectacular land and seascape consisting of shallow seas, small fjords and bays and an inner part of intertidal areas dotted with about 3,000 islands, islets and skerries. The area contains about half of Iceland's intertidal area and tides can be six metres. The bedrock was formed during rift volcanism in the late Tertiary. The area consists mainly of pile of basaltic lava that was deeply eroded by glaciers during the quaternary age thus creating diverse landscape with several geothermal sites, some visible only at low tide.

The big intertidal zone is high in biodiversity and productivity and has extensive algal forests and other important habitats for fish and invertebrates. The area supports 230 species of vascular plants and around 50 breeding bird species including common shag, glaucous gull, white-tailed eagle, common eider, black guillemot and grey phalarope. The area is important staging area for brent goose and red knot. The common seal and the grey seal have their main haul-out on the islands and skerries.

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