The Forest of Dean is a geographical, historical and cultural region in the county of Gloucestershire, England. It is a roughly triangular area bounded by the River Wye to the west and north, the River Severn to the south, and the City of Gloucester to the east. It is characterised by over 110 km² of mixed forest, one of the most ancient surviving forests in England, with areas of associated woodland stretching across the border into Wales. It gives its name to the local government district, Forest of Dean.