The Coryton Line is a commuter railway line in Cardiff from the city centre to Heath, Birchgrove, Rhiwbina, Whitchurch and Coryton. It was originally opened as part of the main line of the Cardiff Railway. The line is currently operated by Arriva Trains Wales (ATW) as part of the Valley Lines network. ATW replaced the previous franchise, Wales & Borders Trains in December 2003. Rolling stock seen operating the line are normally class 143 or 142s. However due to the occasional shortages of rolling stock it has been known to see class 150s or even 158s operating services.