Deepdraw

A stronghold on a rim spur above the deepest well of its basin: dry-stone walls, a rock-cut cistern below, stone-lined channels, store-chambers dug back into the rim, and a watch platform over the ramps and the pan. After the storms it shrinks to a keeping garrison of a hundred or more; in the dry months well over four thousand people camp around it in their customary rings. The custodians who gather there check the counts of half the basin's strongholds, and nobody checks Deepdraw's own too closely. Its walls have never fallen, and the rim below them is strewn with the bones of raiders who tried.