4 Best Sights in Grindavík, Reykjanes Peninsula and the South Coast (with the Golden Circle)

Across a wide tension crack that opened due to the divergent movements of the North American and Eurasian plates is a narrow footbridge built as a symbol for the connection between Europe and North America. You can (symbolically) walk from one continent to another in seconds, marveling at the tectonic forces at work on this island; the average rifting of the plates amounts to about 2 cm (0.8 inch) per year. The bridge is just off Route 425, and there's plenty of information on-site as well as some classic photo ops (many visitors pretend to hold the bridge up).

This mountain was formed in a single geologic event, and while exploring this magical stretch of coastline, you can see evidence of the different phases of the eruption. Tuff forms during an explosive eruption, and pillow lava forms when lava flows underwater. Out on the sea, you can see majestic black cliffs that serve as castles for birds. A bit farther out you can see the famous Eldey Island, where the great auk (a now-extinct species of bird) used to live. The auks survived the longest in Iceland, but the last great auk was killed on June 3, 1844, for a Danish natural history collector. Eldey is now a bird sanctuary. To reach Valhnúkur, take the road that leads off Route 425 through lava fields. Turn right (the turn is marked, \"Reykjanesviti\"), at the T-intersection, and then go 900 meters (2,953 feet) on an unpaved road, past the impressive Reykjanesviti lighthouse. On the way back, take the left branch at the T-intersection, and in 500 meters (1,641 feet) you'll reach Gunnuhver, Iceland's biggest mud pool.

Five kilometers (3 miles) west of Grindavík, this naturally carved lava tub is constantly filled and drained by ocean surf. Folklore says that the geological pool was the giantess Oddný's favorite spot to bathe. On windy days it's thrilling to watch the incredible force of the sea—just be careful of slippery rocks.

This 10-km-long (6-mile-long) row of craters formed in the Reykjanes Fires, a volcano-tectonic episode in AD 1210–40. The whole area has a spooky and majestic vibe thanks to the steam escaping the craters as well as a nearby borehole. Eldvörp is a bit hidden, but several well-marked walking trails pass near it, including the Reykjavegur. It's also accessible on foot, by bike, and by car on a dirt track from the Grindavík–Blue Lagoon link road.