Eldborg Crater

The cone stands 50 m high and the crater inside it drops 30 m. It is built of spatter and scoria thrown out along an eruption fissure, so Eldborg is not a lone hill but one crater in a row. From the summit a smaller crater shows to the north-east along the same fissure. The path up runs beside a lava channel, the groove the flow used when it left the vent and ran 2.5 km to the sea. Behind the cone stands Geitahlíð, a tuya of 385 m built under Ice Age ice, and one of the fissures cuts into its flank. Litla-Eldborg, on the parallel crater row, has been damaged by quarrying.

• Parking is free. The car park at the trail has room for four or five cars, and there are two more parking areas along the gravel road.
• The last stretch is gravel and rough enough to trouble the undercarriage of a low two-wheel-drive car.
• The path is only partly marked and unclear where it leaves the car park. Stay on it: the moss either side is fragile.
• Level to the foot of the cone, then steep to the rim. Wear boots with grip.
• The rim is exposed. Wind comes straight across the open lava field, so bring a windproof layer.

The turn-off leads onto a gravel road, with a small parking area immediately on the left. The whole crater is in view from there, which makes it the better spot for photographs from a distance. The trailhead car park is a kilometre further along the same road. The path to the rim starts there and takes about 15 minutes one way, level to the foot of the cone and steep for the last part. A third parking area sits on the road between the two craters.

Better: late afternoon, and autumn above all. The low sun brings out the colour in the scoria and the moss, and the light falls along the coast to the south.

Avoid: low cloud. Most of the reward at the top is the view, and cloud takes it away. The crater is rarely busy at any hour.

Eldborg and the ground around it have been a protected natural monument since 1987, inside the Reykjanesfólkvangur reserve. The site is unfenced and there is no ticket, so the protection rests on visitors. Keep to the path: the moss on the lava breaks under boots and does not recover. Take your litter back down with you.