Þingvellir National Park

Þingvellir is both a national shrine and a geological showpiece. The Alþing, Iceland's general assembly, was established here around 930 and met on the plains by the river Öxará until 1798, so the place carries a great deal of national memory. It also sits on the Atlantic Ocean ridge, and the gorges and cracks in the landscape are the visible result of the earth's crust pulling apart.

It is one of the three stops on the Golden Circle, so it is busy in summer. The park has a visitor centre with an exhibition on its history and nature, and parking near the most popular attractions carries a service fee. Diving and snorkelling in Silfra are allowed but have requirements, so check the park's own page first. Allow time for a walk rather than a quick photo stop.