A charter dated at Lambeth 5 August 1205 confirmed that Nicholas had paid a fine of 10,000 marks for his inheritance, with the exception of the castles of Knaresborough and Boroughbridge, which were retained by the King.

She gave birth to her son, Humphrey, in September, assisted by a holy relic of the girdle of the Virgin, brought especially from Westminster Abbey.

The enclosure wall was punctuated by solid towers along its length, and a pair, visible today, formed the main gate.

At the junction between the inner and outer baileys, on the north side of the castle stood a tall five-sided keep, the eastern parts of which have been pulled down.

In 1789, historian Ely Hargrove wrote that the castle contained "only three rooms on a floor, and measures, in front, only fifty-four feet.

"[13] The upper storey of the Courthouse features a museum that includes furniture from the original Tudor Court, as well as exhibits about the castle and the town.