Most people visit Iceland in summer, when once or twice a week it actually stops raining and the sun shines in a way that makes you think, briefly, about taking off your sweater. The hills show off their green, yellow and red gravel faces to best effect, and you can even get around easily without a snowplough. But if you really want to see what makes this odd country tick, consider a winter visit. True, you’ll find many places cut off from the outside world until Easter, people drinking themselves into oblivion to make those endless nocturnal stretches race by (though they do the same thing in summer, filled with joy at the endless daylight) and tourist information booths boarded up until the thaw. On the other hand, you can do some things in winter that you will never forget.

Up in the northeast, Lake Mývatn is surrounded by craters, boiling mud pools and other evidence of Iceland’s unstable tectonics. Near its northeast shore lie crevasses, flooded by thermal springs welling up out of the earth. They are too hot for summer bathing, but in winter the water temperature drops to just within human tolerance, and the springs are best visited in a blizzard, when you’ll need to be well rugged up against the bitter, driving wind and swirling snow. Clamber up the steep slope and look down over the edge: rising steam from the narrow, flooded fissure five metres below has built up a thick ice coating, so it’s out with the ice axes to cut footholds for the climb down to a narrow ledge, where you undress in the cold and, shivering, ease yourself into the pale-blue water. And then… heaven! You tread water and look up into the falling snow and weird half-light, your damp hair nearly frozen but your body flooded with heat. Five minutes later, you clamber out, feeling so hot you’re surprised that the overhanging ice sheets haven’t started to melt.

Mývatn is about 6hr by road from Reykjavík, and 2hr from the nearest town, Akureyri. Buses run in summer; you’ll have to hire a car during the rest of the year.