A refurbished Grade II-listed lido in Rhondda Cynon Taff will reopen on Monday offering free swimming to users for the rest of the year.
About 450 people will get the chance to use the £6.3m facility at Ynysangharad War Memorial Park, Pontypridd, ahead of its general opening on Tuesday.
The original site had one large pool but the revamped lido has three pools, changing rooms and sun terraces.
It was paid for by Welsh government, Heritage Lottery and council funding.
The site first opened in 1927 but closed in 1991 after falling into disrepair.
Some people were unhappy the paddling pool next to the children's park would not be saved after the council said it could not afford to revamp and run both.
The authority hopes the lido will boost the number of visitors to the town, bringing extra trade for businesses.
There were once dozens of lidos around Wales but the growth of indoor swimming pools and a rise in holidays abroad saw visitor numbers fall.
The last one to shut in Wales was Brynamman lido in Carmarthenshire in 2010 because of a £20,000 repair bill, but campaigners have formed a committee with hopes of reopening it.