Seat of the Assembly of Madrid, Parliament building in Palomeras Bajas, Spain

The Seat of the Assembly of Madrid is a modern building with a distinctive triangular shape and a glass-walled main chamber. The interior is functionally designed and serves as the workplace for regional representatives and their administrative duties.

The Assembly met at the Caserón de San Bernardo until a planned move to Retiro was vetoed by the city council. President Pedro Díez then proposed the southern site in Palomeras Bajas, and the first stone was laid in April 1995 amid a protest by 200 residents demanding public housing. The building opened on 28 September 1998, costing three billion pesetas.

The building contains important artworks, including the unfinished mural La Ciudad Inacabada by Lucio Muñoz and a painting by Antonio López García. These pieces shape the visual character of the spaces where daily political decisions take place.

The complex stands in Palomeras Bajas, in the Puente de Vallecas district south of the city centre, on land formerly held by the Instituto de la Vivienda de Madrid. The plot was smaller than the discarded Retiro site, so some rooms and the car park were reduced in size. Visitors should confirm guided-visit arrangements with the Assembly before travelling.

The main chamber is a glass cube set inside a triangular building, a design carried over from the rejected Retiro plan and scaled down for the smaller Palomeras Bajas site. The car park and several rooms were also reduced in size, though the new plot sits higher than the old Caserón de San Bernardo.