2019 Nos Galan road races: Nigel Owens is mystery runner
Rugby World Cup referee Nigel Owens was this year's Nos Galan road race mystery runner.
Mr Owens carried the race's torch from St Gwynno's Church, Llanwonno, to Mountain Ash, officially starting the New Year's Eve event.
About 1,700 runners were expected to take part in the 5km races for the event's 61st year.
Previous mystery runners have included stars from rugby, football and boxing, along with Olympic athletes.
Mr Owens described it as "great privilege" to start the event.
He added: "I was asked a few years ago but we had (rugby) games on New Year's Eve and New Year's Day then.
"It's a great honour and I didn't have to think twice.
"It's important to keep the tradition going, it's part of our history and heritage."
The streets of Mountain Ash are a long way from his most recent sporting appearance at the Rugby World Cup in Japan.
And the honour highlights how much he has achieved since he refereed his first match in Carmarthen in 1987, when he was just 15.
Rhondda Cynon Taf council's cabinet member for leisure, Ann Crimmings, said: "Nigel Owens MBE is one of the most celebrated personalities in the world of rugby union and sport in general.
"He commands significant respect and admiration both on and off the pitch for his sporting knowledge, his fair approach and the stance he takes against prejudice - especially within the LGBT community.
"We are proud to welcome him as mystery runner to the 2019 Nos Galan road races and we know spectators young and old will be thrilled to join such an icon at this event."
Nos Galan - started by school teacher Bernard Baldwin in 1958 - began as an amateur race around the block, organised on a shoe-string budget raised from jumble sales and based upon the goodwill of the town.
It was inspired by a New Year's Eve race in Brazil and Mr Baldwin wanted to create the "longest race in the world" by staging an event on 31 December which "began in one year and finished in another".
About 10 people entered the first race but more turned up on the day - now it includes races for children, elite men and women, and a general fun run, with 10,000 spectators expected to line the streets.
The race also celebrates the life of Welsh runner Griffith Morgan, who died 250 years ago.
He is buried at St Gwynno's Church in Llanwonno, Pontypridd, where a wreath is laid on his grave every year before the torch is carried to the start line in Mountain Ash.