When the Norse began settling Iceland in the Ninth Century, they found a bitterly cold place with few trees to serve for lumber or firewood. There was, though, plenty of grazing land for sheep, which soon proliferated on the island.
With little firewood, the settlers began burning sheep dung for fuel, including for smoking lamb. Atlas Obscura tells us that this is the origin of hangikjöt, a traditional variety of cured lamb. This food, which is commonly served at Christmas, consists of sheep leg or shoulder which is smoked over burning sheep dung, then served with potatoes, peas, and flat bread.
Photo: @HellesKitchen