If you mean the United States .The Potomac flows through Washington DC but your question probably is something more difficult.
Albany, the capital city in New York, is located on the Hudson River.
Albany
Washington D.C. is the capital city of the United States. Washington D.C. is located on the bank of the Potomac River.
Wichita, Kansas is located on the Arkansas River.
London, the capital city of the United Kingdom, is on the River Thames.
Albany is the city located on the Hudson River that serves as the capital of the state of New York. It is one of the oldest surviving settlements of the original British colonies in the United States.
The capital is Kiev and it is located on the Dnieper River
Topeka is the capital city in Kansas. It is located on the Kansas River.
The Potomac River runs through Washington, D.C.
Topeka, the capital city in Kansas, is located on the Kansas River.
Austin is the state capital of Texas. It is located on the Colorado River.
The Congaree River is not in South America. It is in the United States. Columbia is the capital city of South Carolina. The Saluda River and the Broad River merge at Columbia to form the Congaree River.