>>1838092usually small cottages in remote areas which have been reappropriated into shelters for walkers/climbers.
typically they have sleeping platforms and fireplaces and/or stoves and maybe some cooking utensils.
people often leave spare supplies inside such as tinned food in case anyone might be in need.
some are maintained by volunteers such as the MBA (mountain bothy association) and some are maintained by landowners. anyone is free to use them.