Since 1864 this museum is installed on the site of the impressive ruins of the former Carmo Church, which was founded in 1389 and partly destroyed by the huge earthquake of 1755.

The museum was created by the Association of Portuguese Archaeologists to shelter works of art in danger of disappearing, becoming the oldest museum of Art and Archaeology of Portugal.

It houses a rich and varied collection of artefacts and works of art, dated from Prehistoric times to the present day, among which deserve special notice the Chalcolithic artefacts; the Roman and Hebraic inscriptions; the royal medieval and modern sculptures and tombs; the blue and white tile panels; the Pre-Colombian artefacts; the Peruvian and Egyptian mummies; and, a rare Hindu low-relief. Reference should also be made to the original grave of Saint Constable.

The atmosphere of a Romantic ruin confers a special aura to the place to which no visitor remains indifferent.