Emberton Country Park is a great place to explore and visit.
There is a sandy and shingle park , a pirate ship park with huge tunnel slide and another more traditional park along with lakes. suitable for wheelchair users, buggies, bikes, scooters.
Use postcode MK45 5FJ.
Its between £2.50 & £4.50 depending on the season to park your car, there are toilet facilities and a really yummy café selling homemade cakes, hot food and even sugar free and vegan treats.
There is a dedicated car park close to the entrance however you can pretty much park anywhere which is perfect for then your taking a picnic. Just pack a blanket and toys and stay all day.