There are two main routes for passenger train services to West Wales:
Travel to Aberystwyth involves (usually) one change of train, generally at Wolverhampton; journey time to Aberystwyth from London is around five hours. Apart from the industrial scenery of the West Midlands, much of the journey is very beautiful, and the run from Machynlleth to Borth along the Dyfi estuary is particularly fine; the journey northwards to Pwllheli is also exceptionally attractive, with many dramatic sea views.
Trains run to and from Aberystwyth approximately every two hours.
Travel to Carmarthen also requires one change of train, at Swansea (though there is generally one through train each way daily). Journey time is about four hours from London to Carmarthen. The journey is pleasant, with a fine view of the famous White Horse at Uffington, just east of Swindon, and a very pretty run into Carmarthen along the Tywi estuary.
Trains run to and from Carmarthen roughly every hour.
Alphaline, which provides local and medium-distance services, has its own growing Web site with details of trains and other information, and full details of services to Carmarthen are also available from a non-commercial site.
Car hire can be arranged at many centres in Wales; details of some of these are listed on the Avis Web Site.