The Danube Delta is the second largest river delta in Europe, after the Volga Delta, and is the best preserved on the continent. The greater part of the Danube Delta lies in Romania, with a small part in Ukraine. Its approximate surface area is 4,152 square kilometres, of which 3,446 km2 (1,331 sq mi) is in Romania. With the lagoons of Razim–Sinoe, located south of the main delta, the total area of the Danube Delta is 5,165 km2 (1,994 sq mi). The Razim–Sinoe lagoon complex is geologically and ecologically related to the delta proper; the combined territory is listed as a World Heritage Site.

Romania is a country located at the crossroads of Central, Eastern and Southeastern Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to the east, and the Black Sea to the southeast. It has a predominantly continental climate, and an area of 238,397 km2 (92,046 sq mi) with a population of 19 million people (2023). Romania is the twelfth-largest country in Europe and the sixth-most populous member state of the European Union. Its capital and largest city is Bucharest, followed by Cluj-Napoca, Iași, Timișoara, Constanța, Craiova, Brașov, and Galați.