U.S. Route 101
The nearly highway's northern terminus is in Tumwater, Washington: the route remains along the Olympic Peninsula's coastal perimeter west, north, and east; the northernmost point on the highway is in Port Angeles. The southern terminus of US 101 is in Los Angeles at the East Los Angeles Interchange, the world's busiest freeway interchange.
U.S. Route 151
U.S. Highway 151 starts at an intersection with Interstate 80 (I-80), in an isolated part of Iowa near both Williamsburg and Conroy. It then continues through the area around the Amana Colonies, where it has a brief overlap with US 6. Once meeting up with US 30 and US 218, the route cuts around the city of Cedar Rapids, while the business route 151 goes through the city. The route splits from the other roads and continues toward Dubuque as an expressway. This stretch crosses many major rivers including both the Wapsipinicon and the Maquoketa. The road eventually goes into the Driftless Area where it meets up with US 61 around the Dubuque Regional Airport. The combined road then heads into the state of Wisconsin where it continues with the US 151 name.