Brazzaville is the capital and largest city of the Republic of the Congo and is on the north side of the Congo River, opposite Kinshasa. Its population is estimated to exceed 1.8 million. Over a third of the population of the Republic of Congo lives in the capital, and it is home to 40% of non-agricultural employment. It is also a financial and administrative capital.

To distinguish between the two African countries with "Congo" in their names, the Republic of the Congo is sometimes called Congo-Brazzaville, as opposed to Congo-Kinshasa (the Democratic Republic of the Congo, known from 1971 to 1997 as Zaïre, the capital of which is Kinshasa). Kinshasa lies on the southern bank of the Congo, directly across from Brazzaville. This is the only place in the world where two national capital cities are on opposite banks of a river, within sight of each other.

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