The Cathays (/kəˈteɪz/ kə-TAYZ) electoral ward of Cardiff consists of some or all of the following areas: Blackweir, Cardiff city centre, Cathays, Cathays Park and Maindy in the parliamentary constituency of Cardiff Central. It is bounded by Gabalfa and Birchgrove to the north; Plasnewydd and Adamsdown to the east; Butetown to the south; and Riverside to the west. The River Taff forms its western boundary to where it meets the South Wales Main Line, the South Wales Main Line forms the southern boundary to where it meets the Valley Lines northbound branch, this railway line then forms the eastern boundary as far as the A48 road. The Northern boundary follows the A48 as far as Allensbank Road where it follows this road south then turns north again along Whitchurch Road. It turns west along Crown Way, then south along the A470 until North Road where it bears west, passing just south of the student halls, until it meets the River Taff.