The Nos Galan races celebrate Griffith Morgan (Guto Nyth-brân, 1700-37) of Llanwynno.
Guto Nyth-brân achieved fame for his speed as a runner. When he was 37 he accepted a challenge to run 12 miles from Newport to Caerphilly. He won the race easily, but the congratulatory back slapping proved too much for him and he died at the finish. He was buried near Mountain Ash. The Nos Galan races were first run in 1958 and have grown from a single 100 yard dash and four mile run, to a series of events, the highlight of which is a 5km race. Each year a famous sports personality attends the races, placing a wreath on Guto's grave.