Passengers can now catch a train to Birmingham airport from Aberystwyth
A rail service linking Aberystwyth and London, which was scrapped in 1991, could be restored.
Currently, trains run every two hours from the Ceredigion town to Birmingham, while a new direct link to the city's airport also began this week.
Arriva Trains Wales has now announced a consultation for two services a day from Aberystwyth to London Marylebone.
Ceredigion MP Mark Williams said people in the county would welcome a direct service to the UK capital.
Announcing the consultation, Arriva Trains Wales said research showed there was strong customer demand for the service.
MP Mr Williams said: "A direct service to London is something many people in Ceredigion will welcome, and I hope that the consultation will provide a successful outcome.
"Arriva must put a considerable effort into improving and extending existing services, which are currently substandard, but providing a link to London has obvious benefits for Ceredigionís residents and the local economy.
"I was pleased to travel on the inaugural Birmingham International service. Anyone who regularly travels between Aberystwyth and London will have experienced the dreaded missed connection at Birmingham New Street, which could add several hours to journeys."
Mike Bagshaw of Arriva Trains said he was delighted to announce "exciting" further plans for the Cambrian line route.
He added: "Market research and our own knowledge of the local market, has shown that there is a strong customer demand for a comfortable and reasonably priced direct service between mid Wales and London, avoiding the need to change trains in Birmingham.
"The restoration of this through link will bring significant benefits to both the local economy and tourism."
Trains in mid Wales use the Cambrian line, which links the region with stations across England.