Naughty castle also called Fort child. A set of recreation, sports, fitness function, puzzle through the formation of three-dimensional combination of science as one of the new generation of children's activity center. We can say that it is a comprehensive model, strong children's playground for children, like drilling, climbing, rolling, sliding, rocking, swing, jump, shake nature design. Naughty fort to teach their children to independent personality, physical exercise, brain puzzle. Random, characteristic, interaction and security, no restriction site (only indoor), or irregular site, can install, simple management, no power equipment, convenient repair.