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

Romania

România

Population: 19,286,123

Region: Europe

Subregion: Eastern Europe

Capital: Bucharest

Top Level Domain: .ro

Currencies: Romanian leu

Border countries

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 Hungary has three horizontal stripes of red, white, and green.

Hungary

Population: 9,749,763

Region: Europe

Capital: Budapest
The flag of Moldova has three vertical stripes of blue, yellow, and red, with the national coat of arms centered in the yellow stripe.

Moldova (Republic of)

Population: 2,617,820

Region: Europe

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

Serbia

Population: 6,908,224

Region: Europe

Capital: Belgrade
The flag of Ukraine has two horizontal bands of blue and yellow.

Ukraine

Population: 44,134,693

Region: Europe

Capital: Kyiv