At the Van Renswoudenstraat, a street hidden, next to the way up to the Koepoortbrug (bridge) is a small but sufficient playground which has become a mandatory stop for me when I visit Delft with my daughter, age 3.
The playing equipment is suitable for children from 2 years old until the age of 6. Older is possible but I think they get bored after a while.
There is a slide with a stairs, but you can also choose the small climbing wall. There are two swings, a seesaw which also works when you use it alone and an easy suspension bridge.
A part of the ground is covered with artificial grass, so you don’t get sand in your shoes.
My daughter can play there for at least half an hour. The Nieuwe Kerk with the clock on it is in your view. It is a safe place as you can close the gates so your children cannot walk on the street.
If you stay at the hotel Delft center its is only two minutes walk.
Playground Van Renswoudestraat