One of the oldest houses and the first city hall was completed in 1267, but it is probably even older. The facade was changed frequently.
Wikipedia (German) http://de.wikipedia.org/wiki/Grashaus
More information at route-charlemagne.eu (German) http://www.route-charlemagne.eu/Stationen/Grashaus/
Address Fischmarkt, 52062 Aachen, Germany
Coordinates 50°46'27.829" N 6°4'57.918" E