Rhydian Roberts will appear in his first full concert in his home country
An inaugural four-day family festival in Pontypridd opens later, which will see Welsh X Factor runner-up Rhydian Roberts headline a concert on Sunday.
The Big Weekend in the Park was set up by the local council after the Full Ponty festival was cancelled.
Friday's opening event is an open-air cinema showing family-friendly films in the town's Ynysangharad Park.
A rock concert takes place on Saturday night followed by a family fun day and the Music in the Park night on Sunday.
On Monday, a 90-piece youth orchestra will perform a classical concert in the Muni Arts Centre to commemorate the 40th anniversary of the town being twinned with Nurtingen in Germany.
Friday - Movies in the Park, Music in the Muni
Saturday - Rock concert, Muni Arts Centre
Sunday - Fun day and Music in the Park
Monday - More Music in the Park
Appearing alongside Rhydian will be chart-topping singer Sandi Thom, former Fame Academy contestant James Fox, Welsh singer-songwriter Mal Pope and TV presenter and comedian Chris Corcoran.
Rhondda Cynon Taf mayor Margaret Davies said: "Ponty's Big Weekend promises to be the biggest festival of its kind ever to come to Pontypridd or the county borough as a whole.
"This is the first event of its size in Wales outside of Cardiff and Swansea and Rhondda Cynon Taf will play host to a massive four-day event filled with activities and entertainment."
"We are sure that this broad spectrum of events will attract visitors of all ages because it really is a family weekend of music, film and song.
"There's something for everyone and that's the secret to the success of Ponty's Big Weekend which will certainly live long in the memory of all
The fourth Full Ponty two-day festival had been due to take place in the town in May.
The event had previously attracted local stars such as Tom Jones and Lostprophets but its backers, Pop Factory and Avanti, felt they did not have an adequate line-up to follow on from such high-profile acts.
The council has said while the Full Ponty had been aimed more at the 18-25 market, the Big Weekend in the Park was looking to attract a family audience.
The event is free but the public need to reserve tickets for Movies in the Park and Music in the Park, which are available from Pontypridd's Muni Arts Centre, Aberdare's Coliseum, Treorchy's Park and Dare Theatre or via Ticketline and Ticketmaster.