Cuéllar is a town that lies to the north of Segovia province. Its walls, castle and San Martín church were declared to be National Historical and Artistic Monuments as far back as 1931.
The Dukes of Alburquerque 15th and 16th century castle is situated in the highest part of the town. It has a rectangular ground plan and four turrets, one at each corner. Three of the latter are round, though worthy of special mention is the parade ground and the southern façade gallery, both of which are Renaissance elements. Dramatised tours of the castle are given all year round.