The first railway built in the county was the Saundersfoot Railway, which linked the Grove Colliery with the harbour at Saundersfoot. Another small scale railway was built between the slate quarry at Abereiddy and the Harbour at Porthgain.
It was not until 1853 that the first major railway line was built in Pembrokeshire. The South Wales Railway linked Haverfordwest with the big industrial cities of Swansea and Cardiff.
Other lines were built, linking the rest of the county with the outside world.