The Evoramonte Castle, near Estremoz in the Alentejo, was built in the 14th century in the Gothic style. It was partially destroyed by the earthquake of 1531 and rebuilt as palace of Italian Renaissance inspiration. The square layout, the round corner towers, and the typical Manueline cord knots sculpted in stone are from that period. The agreement that ended the Liberal Wars was signed in 1834 in this castle.
The Silves Castle, in the Algarve, is Portugal’s main and best preserved Moorish castle. The castle was first conquered by the Portuguese and northern European crusaders in the late 12th century, but was taken back by the Moors two years later. Silves only became definitely part of Portugal in the mid-13th century. The earthquake of 1755 damaged the castle severely.
Both castles are national monuments since 1910 and were subject to restoration works during the 1930s and 1940s.
The set was designed by José Luís Tinoco (stamps) and José Bénard Guedes (coats of arms), lithographed by the Mint on enamelled paper sheets of 5×10 stamps with perforation 12×11½ and a phosphor band, and circulated from 16 January 1987 to 31 December 1992. For each castle, 85 thousand booklets were printed.