Hexmancer

from the "design notes"

Hexmancer is designed to procedurally generate a fantasy borderlands/wilderness region in "fantasy Western Europe," with occasional wasteland and weirdness, on the fly during play. It assumes that you're placing dungeons/modules and perhaps a feature or two, but otherwise starting out with the PCs in a village surrounded by a blank hex map.

This system is based on the one found in "Wilderness Hexplore Revised".