Day out with toddler in/around Aylesbury in the sunshine

[myhandslooksoold]

Hello
Can anyone local please give me any recommendations for a day out in the sunshine tomorrow with a 2 year old? I am meeting an old friend who also has a 2 year old. She is coming from Knebworth and I am travelling from thame (staying there for a few days). We are looking anywhere in the triangle around Aylesbury.
I am looking for a park with a water play feature or a visitor attraction that is suitable for little ones.
If you can help I'd really appreciate it thank you.

Bump

I live in this area. First tip would be avoid Aylesbury, there are lots of nicer places. I have heard that Cutteslow park on the edge of Oxford (near Water Eaton park and ride) is really excellent. It has a paddling pool, mini railway, playground etc etc. Or Waddesdon National Trust has fab playground for kids and is very popular with families here. Other ideas: Bucks Railway Centre, Mead Open Farm, Gullivers World (have heard lots of good things about that one too). Wendover woods if they are v outdoorsy (ok playground and nice cafe plus lots of walks). Whipsnade or Wooburn. I am struggling to think of any other places with water play over that way... Hope that helps