Worcester's city walls are a sequence of defensive structures built around the city of Worcester in England between the 1st and 17th centuries. The first walls to be built around Worcester were constructed by the Romans. These early walls lasted beyond the fall of the Empire, and the defences encouraged several early Christian foundations to establish themselves in Worcester during the troubled 6th and 7th centuries. The Anglo-Saxons expanded Worcester in the 890s, forming a new walled, planned city, called a burh. The burh utilised the southern stretches of the old Roman walls, but pushed further north to enclose a much larger area. The Anglo-Saxon city walls were maintained by a share of taxes on a local market and streets, in an agreement reinforced by a royal charter.