Helical Staircase

Every photographer has to "do" one and this is mine. It's not a spiral as spirals get bigger as they wind out?/on?" A helix stays within a cylinder (otherwise you'd need your stairwell to get wider and wider). Or so I heard (QI perhaps? Certainly not Wikipedia!)

PS bags me the job of recording all the paint combinations that the good burghers of Kirkudbright (The Artist's Town) paint their houses with! link to kirkcudbright