Hatfield House is a country house set in a large park, the Great Park, on the eastern side of the town of Hatfield, Hertfordshire, England.
An earlier building on the site was the Royal Palace of Hatfield. Only part of this still exists, a short distance from the present house. That palace was the childhood home and favourite residence of Queen Elizabeth I. Built in 1497 by the Bishop of Ely, King Henry VII's minister John Cardinal Morton, it comprised four wings in a square surrounding a central courtyard.
More information on the Wikipedia page [1]. The website is [2].