There are a number of lovely horse riding stables around St Ives. Here you can book a lesson, join an own your own pony day, or go on a hack. We often take our children to the Old Mill Riding Stables in Lelant Downs. They have an indoor arena, an outdoor jump area and take the horses into the woods.
There are two other stables which I hear good things about - Penhalwyn Trekking Centre and Standing Stone Stables.
There is also the amazing Cornwall Swimming Horses in Penzance which takes horses into the sea.