Totternhoe Knolls is a chalk hill, located north-west of Totternhoe village in the county of Bedfordshire, with the remains of a medieval castle. It is designated as a Site of Special Scientific Interest, as an example of chalk grassland. It is also a Local Nature Reserve. At the west end of the hill, there were medieval quarries for Totternhoe Stone. This area is called the Little Hills, and it is managed as a nature reserve by the Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire.