ELVAS, an episcopal city and frontier fortress of Portugal, 17o m. E. of Lisbon, and to m. W. of the Spanish fortress of Badajoz. Pop. (193o) 13,423. Elvas is finely situated on a hill 5 m. N.W. of the river Guadiana. It is defended by seven bas tions and the two forts of Santa Luzia and Nossa Senhora da Grata. A fine aqueduct, 4 m. long, was begun early in the 15th century and completed in 1622. The surrounding lowlands are very fertile, and Elvas is celebrated for its excellent olives and plums. The fortress of Campo Maior, to m. N.E., is famous for its siege by the French and relief by the British under Marshal Beresford in 181r.
Elvas is the Roman Alpesa or Helvas, the Moorish Balesh, the Spanish Yelves. It was wrested from the Moors by Alphonso VIII. of Castile in 1166 ; but was temporarily recaptured before its final occupation by the Portuguese in 1226. It twice with stood sieges by the Spanish, in 1658 and 171I. The French under Marshal Junot took it in March 18o8, but evacuated it in August, after the conclusion of the convention of Cintra (see PENINSULAR WAR).