Caerphilly (; , ) is a town in the county borough of Caerphilly, South Wales, located at the southern end of the Rhymney Valley. At the time of the 2001 Census the town had a population of 30,388. It is a commuter town of Cardiff and Newport, which are located some 7.5 miles (12 km) and 12 miles (19 km) away, respectively. It is separated from the Cardiff suburbs of Lisvane and Rhiwbina by Caerphilly mountain. It is traditionally within the county of Glamorgan, on the border with Monmouthshire and it is the largest town in the county borough of Caerphilly, which since 2003 has formed part of the lieutenancy area of Gwent. The town gives its name to Caerphilly cheese, which originated in the area.