Sofia (, Sofiya,) is the capital and largest city of Bulgaria. Sofia is the 15th largest city in the European Union with population of more than 1.2 million people. The city is located at the foot of Vitosha Mountain in the western part of the country, within less than drive from the Serbian border. Its location in the centre of the Balkan peninsula means that it is the midway between the Black Sea and the Adriatic Sea, whereas the Aegean Sea is the closest to it.

Salzburg Conference for Young Analytic Philosophy (German: Salzburgiense Concilium Omnibus Philosophis Analyticis, abbreviated SOPhiA) is an annual conference for students and doctoral candidates in philosophy. Since its inception in 2010, the event has been arranged on the Department of Philosophy at the University of Salzburg in Salzburg, Austria. Most of the talks are held by students and doctoral candidates in philosophy. These are selected by double-blind review. In addition, each conference have featured several keynote speakers, notably Stephan Hartmann, Martin Kusch and Ulla Wessels.

Sofia is the capital and largest city of Bulgaria.

Sofia (Greek: Σοφία or Σοφιά also Isle of Gaia) is an island of the Echinades, among the Ionian Islands group of Greece. As of 2011, it had no resident population.

Sophia may refer to:

• Sophia (name), including lists of real and fictional people so named

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a joint project of NASA and the German Aerospace Center (DLR) to construct and maintain an airborne observatory. NASA awarded the contract for the development of the aircraft, operation of the observatory and management of the American part of the project to the Universities Space Research Association (USRA) in 1996. The DSI (Deutsches SOFIA Institut) manages the German parts of the project which are primarily science and telescope related. SOFIA's telescope saw first light on May 26, 2010. SOFIA is the successor to the Kuiper Airborne Observatory.