The New Forest pony is one of the recognised mountain and moorland or native pony breeds of the British Isles. Height varies from around 12 hands (48 inches, 122 cm) to 14.2 hands (58 inches, 147 cm). The ponies are valued for hardiness, strength, and surefootedness. The breed is indigenous to the New Forest in Hampshire in southern England, where equines have lived since before the last Ice Age. The New Forest pony can be ridden by children and adults, can be driven in harness, and competes successfully against larger horses in horse show competition. The population of ponies on the Forest has fluctuated in response to varying demand for youngstock. Numbers fell to fewer than six hundred in 1945 but have since risen steadily, and thousands now run loose in semi-feral conditions. The welfare of ponies grazing on the Forest is monitored by five Agisters, employees of the Verderers of the New Forest. The ponies are gathered annually in a series of drifts, to be checked for health, wormed, and tail-marked; each pony's tail is trimmed to the pattern of the Agister responsible for that pony. Many of the foals bred on the Forest are sold through the Beaulieu Road pony sales, which are held several times each year.