Most visitors bring a tent (or campervan) to this large, gravelly, panoramic campsite (with laundry facilities, and hot showers for 500kr). It gets very busy in summer, with a capacity of 400 pitches; note that the site is open year-round. Reservations are only required for large groups (40-plus people). No cooking facilities are provided. Wi-fi is available in the visitor centre.
If you're looking for a less-crowded option, consider the campground at Svínafell, 8km east.