Originally a wooden motte and bailey castle built by William the Conqueror, Pickering Castle remained in the hands of various members of the Royal Family until it passed to the Office of Works (now English Heritage) in 1926.
After the conquest, it never saw action and was essentially a royal hunting lodge for the nearby Forest of Pickering, and between 1100 and 1400 most kings stayed there at some point.
In 1322 Edward II went so far as to establish a stud farm with about 50 horses on the site, but otherwise it was always little more than a grand second home.
For Opening Times, Admission Prices, etc. please go to English Heritage's official site, detailed below.