Peterborough Castle, also known as Mount Thorold and Touthill, was a medieval motte and bailey castle in Peterborough, Cambridgeshire, England.

[1] A motte and bailey design was erected close to the cathedral, in what is now the Dean's garden.

[2] Thorold built the castle to protect himself against the monks in the cathedral, during the turbulent post-conquest period.

[3] The castle was destroyed by the 12th century abbot Martin de Bec.

[3] Today only the motte survives of the castle and is now between ten and twelve metres high.