The geographical term Severnside refers to an area adjoining or straddling the River Severn or its estuary in Great Britain. The term is used by different organisations, in different contexts, to refer to quite different areas. The Severn passes through both England and Wales, in some places forming the boundary between the two. Some uses of "Severnside" relate to areas on both sides of the river, and others only to one or other side. It generally refers to the cities on either side of the Severn Estuary. These include Cardiff, Newport and Bristol.