The Fastness of Daymair Keep (2012)

From publisher blurb:

Horthright Daymair, inheritor of the ancient keep of Agmarrar, finds his legacy contested by the black hearted warlord Skalig Fetherbrun. Both are en-route to the keep, each man intending to populate its high battlements with his soldiers and defend it from his nemesis.

But Daymair is far behind Skalig and fears Agmarrar will be lost. Thus he sends word ahead to loyal allies to employ a mercenary force keen to earn a substantial reward. Their task is to occupy the keep and defend it until Daymair arrives.

Daymair Keep is a lovely old-school style black and white stronghold floorplan, a potentially invaluable addition to your GM toolbag whether you choose to run the accompanying adventure or not.