Thousands of football and rugby fans are expected in Swansea to mark the end of an era on Saturday, with final matches at their respective grounds.
Swansea City play a final sell-out match at the Vetch, the last scheduled league game at the 93-year-old ground.
Next season the club moves to a new 20,000 seater stadium in Landore.
The Swans will be joined there by the Ospreys regional rugby side who take on Ulster on Saturday evening in their final game at St Helens, a mile away.
Police said they were expecting thousands of supporters in Swansea throughout Saturday and were advising people not to drive into the city centre but to use public transport.
For both sets of fans the day is set to be an emotional one.
The countdown to the last league match at the Vetch kicked off on Friday when Swans' legends attended a dinner in a marquee at the 93-year-old ground.
Honorary president of Swansea City AFC, David Farmer, said: "I've been going to the Vetch since I was six-years-old, that was back in 1938.
"There have been so many games and so many great footballers have played there - and a few rubbish ones as well.
St Helens will continue to host semi-professional and junior rugby
"It's a typically old fashioned ground but unfortunately it's just passed its sell-by date."
Mr Farmer was a member of the board during the John Toshack era when the Swans rose from what was then Division Four to the top of the First Division.
"For me the most memorable game was the defeat of Leeds United 5-1 in our first game in the old First Division which was something special. That season we were never out of the top six and led the division three times.
"With the wages players get today I don't think that can ever be repeated.
"We've always had a rich seam of players, particularly in the 1950s with the likes of Ivor Allchurch, Mel Charles and Terry Medwin. If we can find a few more of them we'll do well again in the future."
Fans and the club's supporters trust are marking Saturday's sell-out game against Shrewsbury as the last at the Vetch although the Swans will play there again if they end up in the League Two promotion play-offs.
There is no such uncertainty at St Helen's where the Ospreys play for the last time.
The new 20,000 seater stadium at Landore is almost complete
The seafront ground will continue to host semi-professional and junior rugby, as well as cricket, but is unlikely to ever again see crowds like the 10,000 plus who saw Swansea beat the then world champions Australia in 1992.
Ospreys rugby manager Derwyn Jones said: "Many special moments have been witnessed at the ground down the years, from the All Whites beating the Wallabies to the first time an Ospreys side took to the hallowed turf in the professional era.
"Moving will obviously be a big change but will be an exciting new chapter in the Ospreys' history."
Chief Inspector Keith Bowman of South Wales Police said the Swansea Shrewsbury match was sold-out and anyone without a ticket would not be allowed near the ground.
"We will make sure that the disruption of people's activities in the city is kept to a minimum," he said.