A half covers about half the ground a marathon does, which means the model is drawn at twice the detail: individual buildings rather than massed blocks, and streets you can put a finger on and name.
The half marathons routes are being built and photographed. Yours can still be made today from your own file — which is the same model, made for one person.
Upload the GPX from your watch, from Strava or from the organiser, and the engine builds a half model from your actual track. You see it before you pay.