If you've made it along the Ring Road to Vik and are looking to do a little beachside exploration, consider making a stop over to the stretch of volcanic "sand" that lies just southwest of the town under the small but beautiful Reynisfjara Mountain. You'll either have to turn west onto the small road that that connects to Route 1 just north of Vik, or you can turn south onto 215 a bit farther north. Both roads lead roughly to the same place.
Technically, there's not too much to do here besides admire more of the country's incredible scenery, although as you stroll along the beach you'll be able to get up close and personal with some of Iceland's beautifully distinctive hexagonal basalt columns. There are even a few caves that you can duck into, composed of fantastic rock formations of their own. Keep your eyes peeled for nesting puffins and fulmars, and if you're lucky you may even catch a seal or two depending on the season. Beautiful spot.
Note:A word of caution: the current and undertow at Reynisfjara Beach is tremendous, and tourists have actually died here after being caught by so-called "rogue waves" that have surprised them when standing too close to the water's edge. Be mindful of where you're walking, and when in doubt always err on the side of being farther away from the water.