About 3km south of Seltún across the Krýsuvíkurhraun lava fields, a dirt track leads down to the coast at Krýsuvíkurberg (marked on the main road as Krýsuvíkurbjarg). These sweeping black cliffs stretch for 4km and are packed with some 57,000 seabird breeding pairs in summer, from guillemots to occasional puffins. A walking path runs the length of the cliffs.
To get here it's roughly a 2km drive from the main road. The potholed route is doable in a regular sedan, but better negotiated with a 4WD. There is a small fjord to pass; those without a 4WD can stop in the small parking area and hike the final half a kilometre to the cliffs.