The Wales National Pool in Swansea is to allow youngsters under 16 in for free this summer, as efforts are made to get the public to use it more.
Managers say some people do not know the pool is open to the public
The £11m complex has been open over a year but managers say some people remain unaware it is not just for elite athletes and serious swimmers.
From next Monday, the pool joins the assembly-backed free swim scheme for the first time.
Managers say they are happy with the numbers using the pool, although attendance figures are not available.
But they admit that some people do not know that it is open to the general public.
The only 50m Olympic-sized swimming pool in Wales, it was funded by the Sports Council for Wales, Swansea Council and Swansea University.
The centre, which replaced the old Empire Pool in Cardiff, was built with the aim of providing top Welsh swimmers with the very best training facilities and competition venue.
But the pool's Jamie Rewbridge said it had always been intended for use by families, tourists and fun swimmers as well and public sessions had been increased.
"We are pretty much open at all times to the public," he said.
"There are people that are under the assumption that it's not for the public, but it is.
"We've got a mix of sessions from the non-swimmers up to the elite athletes. It's for all ages and all abilities.
"We are able to hold pool parties for kids and there are fun sessions for kids."
He said since Swansea Leisure Centre shut suddenly last November, after it was found £14m worth of repairs were needed, numbers had risen.
Swansea leisure centre closed in November last year
But he said the National Pool still had plenty of spare capacity for former leisure centre regulars to use.
As well as the 50m pool, there is also a 25m warm-pool were daily fun sessions are being held for youngsters throughout the school holidays.
Extra signs have been put-up on Sketty Lane encouraging members of the public to give the pool, which opened in March 2003, a try.
Free swimming for under-16s is available at all council-run pools in Swansea this summer, as it is in many other parts of Wales.
"This is the first time that the National Pool has taken part in the initiative," said a council spokeswoman.
"This year, we are offering lots more activities as well as the free swimming in our leisure centres - such as water polo, rookies life guarding courses, canoeing, aquacise and limited swimming lessons - all for free."