Mývatn

Where it sits. Mývatn is a shallow lake of about 37 square kilometres in northeast Iceland, sitting at 277 metres above sea level roughly 90 kilometres east of Akureyri on Route 1 and 100 kilometres south of the Arctic Circle. It is broad and thin: the mean depth is around 2.5 metres and the deepest point barely exceeds four, which is why the whole basin warms quickly in summer and freezes solid in winter. More than fifty islands and skerries break the surface. The lake drains west through the Laxá river toward Skjálfandi bay, and the district around it, centred on the village of Reykjahlíð with roughly three hundred residents, functions as the service base for the entire northeastern volcanic zone.

How the basin was made. Around 2,300 years ago a fissure eruption southeast of the present shoreline sent a great volume of basalt, the Younger Laxá lava, down the valley. It dammed the drainage and filled the low ground, and the lake formed on top of the flow. Where hot lava ran over waterlogged ground, steam explosions punched out rings of scoria that look exactly like small volcanoes but never had a magma conduit of their own. These pseudocraters are the signature landform of the district, best seen at Skútustaðir on the southern shore, where two loops of 800 metres and 2.3 kilometres thread between them. The same volcanic plumbing still runs hot: Bjarnarflag east of the lake vents steam at the surface, and the Krafla system 20 kilometres north erupted nine times between 1975 and 1984.

The wildlife, which is the real reason it is protected. Mývatn means midge lake, and the name is honest. Non-biting chironomid midges hatch in enormous columns in June and July, and a smaller number of biting blackflies work the outflow of the Laxá. That biomass feeds one of the densest concentrations of breeding ducks anywhere in Europe: thirteen to fifteen species nest here in a normal year, including Barrow's goldeneye, whose only European breeding population lives on this lake and river, plus harlequin duck, long-tailed duck, gadwall and scaup. Iceland passed a dedicated conservation act for Mývatn and the Laxá in 1974, and the wetland was listed under the Ramsar convention in 1977. Diatomite dredging from the lake bed, long a source of local jobs and ecological argument, was finally shut down in 2004.

On screen. The Mývatn district was the northern base for Game of Thrones' Icelandic filming, and the material shot within fifteen minutes of the lake supplied much of what audiences read as the lands beyond the Wall. Grjótagjá, on the eastern shore, provided the cave location for Jon Snow and Ygritte in the third season. Dimmuborgir, ten minutes south, became Mance Rayder's wildling camp in the same season. The surrounding lava fields, the pseudocrater ground and the flank of Hverfjall carried establishing shots and travelling sequences. Crews worked here in winter to get natural snow, and the resulting visitor traffic reshaped the local economy: hotels, guiding companies and the small shops in Reykjahlíð all expanded through the 2010s on the back of it.

What you actually see today. A circuit of Route 848 around the lake takes half a day at minimum and rewards stops in this order for anyone with limited time: the Skútustaðir pseudocraters for the classic Mývatn landscape; Höfði, a wooded promontory where lava pillars stand in the shallows like a flooded stone garden; Kálfaströnd for the same rocks at closer range; Dimmuborgir; Hverfjall; and Grjótagjá. Vindbelgjarfjall on the western shore, 529 metres, is a steep hour up for the best overview of the whole basin. East of the lake, Námaskarð spreads out grey mud pots and yellow sulphur crusts on a hillside where nothing grows, and the Mývatn Nature Baths opened in 2004 offer a milky, alkaline soak at 36 to 40 degrees with the lake spread out below.

Getting there and timing. Route 1 runs along the northern edge of the lake, so Mývatn is a straightforward drive from Akureyri in around ninety minutes and part of the Diamond Circle with Dettifoss, Ásbyrgi and Húsavík. Long-distance buses call at Reykjahlíð in summer. The village has fuel, a supermarket, a swimming pool and several hotels, and it is the last reliable resupply before the eastern highlands. June and July bring midnight light and the heaviest midge swarms, which are harmless but genuinely maddening in still weather, so a head net is worth the few hundred krona. September and early October give calm reflections and the first realistic aurora chances. In winter the ring road stays open but the smaller lake roads drift, and short daylight limits a circuit to the main sights.