Millets Farm, Frillford, Nr Abingdon.
Find this park on the google map I made for you.
We love it here! It really has everything you need for a day out. There's a playground, farm (animals are in enclosed pens), lots of space to run around, a sandpit, a ride on tractor (enclosed, and you have to pay), two restaurants, a supermarket selling their lovely farm food, a garden centre - selling all sorts of things in addition to plants, a fabric/ craft shop housed in a hut. In the summer Millets' 'Maize Maze' opens up and they have my son's favourite - a carousel.
Aside from the playground and the animals, I think everything here is extremely pricey. However, because I am tight-fisted we always take a picnic!
Pictures - from spring. It has taken me too long, oops!
This goes extremely fast - my kids love it:)
Lovely supermarket - if you want to remortgage :)
This carousel is really good fun - a proper full sized one.
Lots and lots of seating area outside the restaurant.