The campaign to reopen two disused railway tunnels and transform them into walking and cycling routes has been given a major grant by the Welsh Government.
The Welsh Government £250,000 has been awarded to Rhondda Cynon Taf Council to help it develop its plans to reopen the Rhondda and Abernant tunnels.
The Rhondda Tunnel runs from Blaencwm in the Rhondda to Abergwynfi in the Afan Valley.
The railway line closed in the late 60s, and the tunnel portals were closed and hidden in subsequent years.
Campaigners have long had an ambition for the tunnel - which runs for more than three kilometres - to be a destination to draw tourists from all over Europe.