The New Castle of Manzanares el Real, also known as Castle of the Mendoza, is a palace-fortress erected in the XI century in the town of Manzanares el Real (Madrid, Spain), next to the Santillana reservoir at the foot of the Sierra de Guadarrama. The castle, of quadrangular floor, is constructed entirely in stone of granite. Its construction began in 1075 on a Romanesque-Mudejar hermitage and today is one of the best preserved castles in the Community of Madrid. It was built on the edge of the Manzanares river, as residential palace of the House of Mendoza, in the vicinity of a primitive fortress, abandoned once constructed the new building. The land bordering the upper reaches of the Manzanares River, rich in pastures and forests were the subject of frequent disputes between different powers arisen after the Reconquista. The castle now houses a museum of the Spanish castles and is home to a collection of tapestries. It was declared a Historic-Artistic Monument in the year 1531.