evidence suggests that a native pony existed in wales before 1600 bc. the original welsh mountain pony is thought to have evolved from this prehistoric celtic pony. welsh ponies were primarily developed in [[wales]], and their ancestors existed in the [[british isles]] prior to the arrival of the [[roman empire]]. bands of ponies roamed in a [[semi-feral]] state, climbing mountains, leaping ravines, and running over rough [[moorland]] terrain.