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The flag of Serbia has a red, blue, and white horizontal tricolor with a coat of arms on the left side.

Serbia

Србија

Population: 6,908,224

Region: Europe

Subregion: Southern Europe

Capital: Belgrade

Top Level Domain: .rs

Currencies: Serbian dinar

Border countries

The flag of Bosnia and Herzegovina has a blue field with a yellow triangle and white stars along the hypotenuse.

Bosnia and Herzegovina

Population: 3,280,815

Region: Europe

Capital: Sarajevo
The flag of Bulgaria has three horizontal stripes of white, green, and red.

Bulgaria

Population: 6,927,288

Region: Europe

Capital: Sofia
The flag of Croatia has three horizontal stripes of red, white, and blue with the national coat of arms in the center.

Croatia

Population: 4,047,200

Region: Europe

Capital: Zagreb
The flag of Hungary has three horizontal stripes of red, white, and green.

Hungary

Population: 9,749,763

Region: Europe

Capital: Budapest
The flag of Kosovo has a blue field with a yellow map of Kosovo in the center and six white stars in an arc above the map.

Republic of Kosovo

Population: 1,775,378

Region: Europe

Capital: Pristina
The flag of North Macedonia has a red field with a yellow sun in the center, featuring eight broadening rays extending to the edges of the field.

North Macedonia

Population: 2,083,380

Region: Europe

Capital: Skopje
The flag of Montenegro has a red field with a gold border and the national coat of arms centered in the field.

Montenegro

Population: 621,718

Region: Europe

Capital: Podgorica
The flag of Romania has three vertical stripes of blue, yellow, and red.

Romania

Population: 19,286,123

Region: Europe

Capital: Bucharest