Cuéllar is a historic town, known primarily for its 15th century castle and the remains of the city's fortifications. An attraction are fictionalized tours with scenes from history organized in the castle.
The buildings in Cuéllar's Old Town come mainly from the 15th and 16th centuries. The most significant building is the Cuéllar Castle, built by the Alburquerque Dukes. Its body shows gothic and renaissance elements as well as the influence of Arab architecture.
Within the largely preserved city walls, there is another important monument in the city, the Church of St. Martin, which now houses the Mudejar Style Center. Elements from the old citadel have also been preserved, such as the Arch of St. Basil. Outside the walls, you can see two other churches, the 13th-century temple of St. Andrew and the Church of St. Stefan.