U.S. Route 161

U.S. Highway 161
U.S. Highway 161
	US 161 highlighted in gray
Route information
	Auxiliary route of US 61
	Maintained by Iowa DOT
Length	185 mi (298 km)
Existed	July 1, 1926–January 1938
Major junctions
South end	Missouri state line south of Keokuk
	US 61 at Keokuk; US 34 at Mount Pleasant; US 6 at Iowa City; US 30 at Cedar Rapids; Iowa 64 at Anamosa;
North end	US 61 at Key West
Location
Country	United States
State	Iowa
Counties	Lee, Henry, Washington, Johnson, Linn, Jones, Dubuque
Highway system
	United States Numbered Highway System; List; Special; Divided; Iowa Primary Highway System; Interstate; US; State; Secondary; Scenic;

U.S. Highway 161 (US 161) was a 185-mile (298 km) U.S. Numbered Highway in Iowa, United States, that ran from Keokuk to Dubuque by way of Cedar Rapids. It was designated in 1925 and signed in 1926 along two primary highways. The route began at the Mississippi River with U.S. Route 61 (US 61) southwest of Keokuk ran north through Mount Pleasant and Iowa City to Cedar Rapids. There, it turned to the northeast through Anamosa and Monticello towards Dubuque. The route ended at US 61 in Key West, a few miles west of Dubuque.

The route changed very little while it was in service. It was paved from end to end by the summer of 1932. In January 1938, it was removed from the United States Numbered Highway System. From Keokuk to Cedar Rapids, it was replaced by U.S. Route 218, which was extended southward. From Cedar Rapids to Key West it was replaced by U.S. Route 151, which was extended westward.