51°28′12″N 3°10′23″W / 51.470°N 3.173°W
The Cardiff Built-up Area or Cardiff Urban Area is the name given to the urban area around Cardiff. The vast bulk of the population and area are contributed by Cardiff, which had a population of 335,145 at the 2011 census. The rest was made up by the towns of Penarth and Dinas Powys, connected to the south-west of the city along Cardiff Bay; as well as the South Wales Valleys towns of Caerphilly and Pontypridd. The total official population of this urban area was given to be 447,487 in 2011.[1] This was an increase of almost 37% on the 2001 population of 327,706. This was mainly due to Caerphilly and Pontypridd becoming part of the built-up area. The population of the Cardiff unitary authority (not co-terminous with the built-up area or the wider urban area) in 2001 was 305,353.[2] Cardiff Council estimated the population of the unitary authority at 317,500 in 2006;[citation needed] at the 2011 census it was 346,090.