Breiðafjörður is encircled by mountains, including Kirkjufell and the glacier Snæfellsjökull on the Snæfellsnes peninsula, and the Látrabjarg bird cliffs at the tip of the Westfjords.
Breiðafjörður has a land and seascape consisting of shallow seas, small fjords and bays, and intertidal areas, dotted with about 3,000 islands, islets and skerries.
The area consists mainly of basaltic lava that was deeply eroded by glaciers during the quaternary age, creating a diverse landscape.
The large intertidal zone is high in biodiversity and productivity and has extensive algal forests and other important habitats for fish and invertebrates.
Just South of Reykhólar, on a small island offshore is also Norður & Co. manufactures sea salt obtained by evaporation of seawater using geothermal energy.
From the small port of Stykkishólmur on the Snæfellsnes peninsula, a ferry crosses Breiðafjörður to Brjánslækur in the Westfjords, stopping at the island of Flatey on the way.
During the Middle Ages, especially in the 12th century, there was a monastery of Augustine monks on the island of Flatey which formed an important centre of Icelandic culture.