Odessa or Odesa (Ukrainian: Одеса; Russian: Одесса; Romanian: Odesa; Greek: Οδησσός; Yiddish: אדעס ) is the administrative center of the Odessa Oblast (province) located in southern Ukraine. The city is a major seaport located on the shore of the Black Sea and the fourth largest city in Ukraine with a population of 1,029,000 (as of the 2001 census).[1]

Odessa was founded by Ottoman vassal, Khadjibey, the Khan of Crimea (Hacibey in modern Turkish spelling) (also known in English as Kocibey) in 1240 and named after him. It passed into the domain of the Ottoman sultân in 1529 and remained in Ottoman hands until the Ottoman Empire's defeat in the Russo-Turkish War of 1798. The Russians renamed the city Odessa in 1794. From 1819–1858 Odessa was a free port. During the Soviet period it was the most important port of trade in the Soviet Union and a Soviet naval base. On January 1, 2000 the Quarantine Pier of Odessa trade sea port was declared a free port and free economic zone for a term of 25 years.

In the 19th century it was the fourth largest city of Imperial Russia, after Moscow, Saint Petersburg, and Warsaw.[2] Its historical architecture has a style more Mediterranean than Russian, having been heavily influenced by French and Italian styles. Some buildings are built in a mixture of different styles, including Art Nouveau, Renaissance and Classicist.[3]

Odessa is a warm water port, but militarily it is of limited value. Turkey's control of the Dardanelles and Bosphorus has enabled NATO to control water traffic between Odessa and the Mediterranean Sea. The city of Odessa hosts two important ports: Odessa itself and Yuzhny (also an internationally important oil terminal), situated in the city's suburbs. Another important port, Illichivs'k (or Ilyichyovsk), is located in the same oblast, to the south-west of Odessa. Together they represent a major transport hub integrating with railways. Odessa's oil and chemical processing facilities are connected to Russia's and EU's respective networks by strategic pipelines.