The promotion of the L&TVJR spurred the people of Cowbridge to move forward with their own scheme, and on 1 July 1861 a prospectus for the Cowbridge Railway was published. It was to run from Cowbridge to connect with the L&TVJR at Maesaraul, north of Llantrisant, crossing the South Wales Railway main line a little east of Llantrisant station, with a spur there to an interchange siding. The capital was to be £30,000, as it was claimed that the cost of construction would be far below the average cost of railway construction locally. The benefits would enable local farmers to get their produce to market cheaply as well as reducing the cost of bringing in coal, and also moving iron ore extracted at
Llanharry to be transported away. In November 1861 the Taff Vale Railway agreed to subscribe up to £5,000 towards the scheme, but subscriptions towards the cost of the railway were otherwise very difficult to secure. Indeed the Parliamentary deposit required to proceed with the Bill had to be loaned by the Taff Vale company. At the committee stages of the Cowbridge Railway Bill, the South Wales Railway once again put forward the proposal that the branch should be built on the broad gauge, which would bring it into the "associated companies" of the broad gauge group. However this last-minute idea was not taken forward. The '''''' (
25 & 26 Vict. c. clxxix) was accordingly passed on 29 July 1862; it had authorised capital of £35,000. Securing subscriptions continued to be a serious difficulty, and the directors decided to approach the South Wales Railway for assistance; they met them on 4 November 1862. They asked the South Wales Railway to permit their company to reach the L&TVJR over the Ely Valley Railway, between Llantrisant and Maesaraul Junction. This would enable them to omit the construction of the northward part of their line above Llantrisant. The broad gauge interest had already shown itself to be hostile to such an incursion, but now the Great Western Railway offered to permit this, and to lay a third rail, forming "mixed gauge", to enable the running of standard gauge trains, for an annual rental of £400. The Cowbridge directors thought this exceeded the interest on the capital outlay if they built the connecting line, so they decided not to proceed with the request at first, but after further consideration agreed that it was worth pursuing. In fact the GWR agreed to reduce the rental charge to £200, and on that basis the Cowbridge directors concluded an agreement in June 1863. The
Board of Trade sanctioned the deviation of the authorised route by which the Cowbridge Railway entered Llantrisant station rather than crossing the South Wales Railway main line. ==Construction==