Elvas is a Portuguese municipality, former episcopal city and frontier fortress of easternmost central Portugal, located in the district of Portalegre in Alentejo. It is situated about 200 kilometres east of Lisbon, and about 8 kilometres west of the Spanish fortress of Badajoz, by the Madrid-Badajoz-Lisbon railway. The municipality population as of 2011 was 23,078, in an area of 631.29 square kilometres. The city itself had a population of 16,640 as of 2011.
Elvas is among the finest examples of intensive usage of the trace italienne in military architecture, and has been a World Heritage Site since 30 June 2012. The inscribed site name is Garrison Border Town of Elvas and its Fortifications.