Two counties in southeast Nebraska are bisected by one of the nation's oldest highways - US 81, also known as the Pan American Highway. Thayer and Fillmore counties serve as part of the 17,000-mile route, which extends from Winnepeg in Manitoba, Canada to the southern tip of Chile, South America at Tierra Del Fuego. The Pan American Highway is the longest continuous stretch of highway in the three Americas: North, Central, and South.

In the very early part of the century, the route was known as the Winnipeg-to-Gulf Highway and ended at Galveston, Texas. On July 10, 1911, a group of Nebraska, Oklahoma, Kansas, and Texas visionaries took trains to Salina, Kansas for the first meeting of the "Meridian Road Association." It was a time when roads were but muddy trails and ruts. With the advent of the automobile, these men realized the importance of graveled or paved surface roadways. Annual meetings have been held since the founding of the Meridian Road Association in 1911.

The roadway was known as the Meridian Highway until 1926, when the federal government decided to number the highways instead of using names. that same year at an international congress in Buenos Aires, Argentina, the South and Central American nations decided to construct a Pan-American highway, extending to the Mexican border at Loredo, Texas. It was at that point that US 81 became part of the Pan-American Highway system.

Over the years, headquarters of the Pan American Highway Association has moved from Newton, Kansas to Salina, Kansas, then Belleville, Kansas. Today, Hebron, Nebraska in Thayer County serves as Association Headquarters.