The East Branch Pecatonica River is a tributary of the Pecatonica River

Pecatonica River

The Pecatonica River is a tributary of the Rock River, long, in southern Wisconsin and northern Illinois in the United States.The word Pecatonica is an anglicization of two Algonquian language words: Bekaa , which means "slow", and niba, which means "water", forming the conjunction Bekaaniba or...

, approximately 62.5 miles (100.6 km) long, in southwest Wisconsin

Wisconsin

Wisconsin is a U.S. state located in the north-central United States and is part of the Midwest. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. Wisconsin's capital is...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

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It rises in the hills of eastern Iowa County

Iowa County, Wisconsin

Iowa County is a county located in the U.S. state of Wisconsin. As of 2000, the population was 22,780. Its county seat and largest city is Dodgeville.Iowa County is part of the Madison Metropolitan Statistical Area.-Geography:According to the U.S...

, approximately 2 miles (3 km) north of Barneveld

Barneveld, Wisconsin

Barneveld is a village in Iowa County, Wisconsin, United States. It is the fourth most populous community in Iowa County, while the second largest village, and largest village located fully within the county. The population was 1,088 at the 2000 census...

 and approximately 25 miles (40.2 km) west of Madison

Madison, Wisconsin

Madison is the capital of the U.S. state of Wisconsin and the county seat of Dane County. It is also home to the University of Wisconsin–Madison....

. It flows south past Barneveld, Blanchardville

Blanchardville, Wisconsin

Blanchardville is a village in Iowa and Lafayette Counties in the U.S. state of Wisconsin. The population was 806 at the 2000 census.The Iowa County portion of Blanchardville is part of the Madison Metropolitan Statistical Area.-History:...

, and Argyle

Argyle, Wisconsin

Argyle is a village in Lafayette County, Wisconsin, United States. The population was 857 at the 2010 census, up from 823 at the 2000 census. The village is located within the Town of Argyle.-Geography:Argyle is located at ....

, and joins the Pecatonica in southeast Lafayette County

Lafayette County, Wisconsin

Lafayette County is a county located in the U.S. state of Wisconsin. As of 2000, the population was 16,137. Its county seat is Darlington.-Geography:According to the U.S...

, approximately 5 miles (8 km) north of the state line with Illinois

Illinois

Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...

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