Highway
Major highways are often named and numbered by the governments that typically develop and maintain them. Australia's Highway 1 is the longest national highway in the world at over and runs almost the entire way around the continent. China has the world's largest network of highways followed closely by the United States of America. Some highways, like the Pan-American Highway or the European routes, span multiple countries. Some major highway routes include ferry services, such as U.S. Route 10, which crosses Lake Michigan.
U.S. Route 6 in Pennsylvania
U.S. Route 6 travels east–west near the north edge of the U.S. state of Pennsylvania from the Ohio state line near Pymatuning Reservoir east to the Mid-Delaware Bridge over the Delaware River into Port Jervis, New York. It is the longest highway segment in the Commonwealth. Most of it is a two-lane rural highway, with some freeway bypasses around larger towns. Except east of Dunmore, where it is paralleled by Interstate 84, it is the main route in its corridor. What is now Interstate 80—the Keystone Shortway—was once planned along the US 6 corridor as a western extension of I-84. The corridor was originally the Roosevelt Highway from Erie, Pennsylvania to Port Jervis, New York, designated Pennsylvania Route 7 in 1924. The PA 7 designation soon disappeared, but as US 6 was extended and relocated, the Roosevelt Highway followed it. The Pennsylvania section of US 6 was renamed the Grand Army of the Republic Highway in 1946; this name was applied to its full transcontinental length by 1953.