Located in the district of Austrias, the Lujanes house and tower is one of the oldest preserved houses in Madrid and in it for several centuries different generations of the lineage of Luján have resided. It is believed to have been built during the fifteenth century, but in reality, both the manor house and the tower date from different periods.

The tower is a solid construction, passed down from the defensive medieval castles, divided into three floors and topped with a turret. Legend has it that King Francis I of France was imprisoned in it after being captured in the Battle of Pavia in 1525, although according to other versions, he was just staying there. Given that it was one of the tallest buildings in the capital, an optical telegraph line between Madrid-Aranjuez was installed on its rooftop in the first half of the 19th century.

The house adjacent to the tower, which occupies number 2, Plaza de la Villa, has an irregular floor plan. The entrance door stands out on its façade, with Gothic decoration and the noble coat of arms of the Luján family. Alongside it, there is another house designed around an interior courtyard. Its façade stands out for the horseshoe arch that serves as an entrance. Inside, there is an impressive Gothic staircase from the former La Latina hospital.

Since 1866, it has been the headquarters of the Royal Academy of Moral and Political Sciences, which initially shared the space with the Royal Academy of Exact, Physical and Natural Sciences and with the Matritense Royal Economic Society of Friends of the Country, which were in the basement.