Valahnúkur was formed by submarine fissure eruption when sea level was standing about 70m higher than today.

The last documented pair of great Auks was killed on Eldey Island off the coast of Iceland on June 1844.

The Svartsengi Power Station  is a geothermal power plant, which is located in the Svartsengi geothermal field, about four km north of Grindavík.

The lake covers an area of 9.7 square kilometers and has a maximum length of 4.7 km (2.9 mi) and a maximum width of 2.5 km (1.6 mi). Its greatest depth is 107 meters, making it the 7th deepest lake in Iceland and reaching below sea level.

Gunnuhver is Iceland´s largest mud pool at present prominent, highest up in the Gunnuhver area group. It is 20 (66 feet ) meters wide across a rim of mud and boiling vigorously.

The sea has a great influence on the landscaping of Reykjanes. By observing the surf crashing on the rocks in the vicinity of Brimketill, you can see the power that resides in the North Atlantic Ocean.