Options to fly into here, rent a car and drive over to Wales, or take a train to Aberystwyth many direct flights. The train would have a couple of changes. You can find a lot of this information on Trainline.com for routes, and also if you search into google train route from Heathrow to Aberystwyth many options are available. The train is roughly 5 hours and 50 mins.

Main Station in the town centre, you can train from the airports.

You are also able to fly in Dublin Ireland and take a Ferry over to Wales. It would then be a two hour drive up to Aberystwyth so I would recommend researching first. Get in touch if you need more help with this option.

This is further up north and a little closer, you most likely will have a stopover. The train is then around a 3 hour roughly direct train to Aberystwyth, from Birmingham International.