The Regional Archaeological Museum of the Community of Madrid occupies an eighteenth-century palace in the historic centre of Alcalá, and holds one of the best collections of Roman material in the Madrid region. The highlight is the extraordinary series of mosaics and painted wall fragments from Complutum — remarkably preserved domestic decoration that transforms what could be dry archaeology into vivid evidence of how a wealthy Roman household actually looked. The colours remain strong after nearly two millennia.
The museum also covers the pre-Roman and medieval phases of Alcalá's history, placing the Roman city in the longer sequence of human settlement in the Henares valley. The building itself, with its courtyard and colonial-era architecture, is worth seeing. The museum is a short walk from the university and the Cervantes birthplace, and pairs well with a visit to the Roman forum site outside town.