I think Ireland can "best" Wales on that front.

Douglas Barry, IMRA chairman, tells me the first reference to hill running comes from Irish legend. Aging hero Finn McCool decided to choose a wife by staging a women’s race up and down a mountain in County Tipperary (some versions say it was a nude women’s race, a tradition that has, alas, lapsed). Unfortunately for Finn, the winner had a mind of her own as well as great legs, and ran off with his handsome cousin, Diarmuid. This set the sport back a bit, but the mountain still bears the name Slievanamon, Mountain of the Women.

https://www.runnersworld.com/advance...d-irish-hills/