List of Interstate Highways
There are 70 primary Interstate Highways in the Interstate Highway System, a network of controlled-access freeways in the United States. They are assigned one- or two-digit route numbers, whereas their associated "auxiliary" Interstate Highways receive three-digit route numbers. Typically, odd-numbered Interstates run south-north, with lower numbers in the west and higher numbers in the east; even-numbered Interstates run west-east, with lower numbers in the south and higher numbers in the north. Highways whose route numbers are divisible by "5" usually represent major coast-to-coast or border-to-border routes (ex. I-10 travels from Santa Monica, California, to Jacksonville, Florida, traveling from the Pacific to Atlantic oceans). Additionally, auxiliary highways have their numbering system where a different number prefixes the number of its parent highway.
Motel
In the U.S., the Interstate Highway System was bypassing U.S. Highways nationwide. The best-known example was the complete removal of Route 66 from the U.S. highway system in 1985 after it was bypassed (mostly by Interstate 40). U.S. 66 was particularly problematic as the old route number was often moved to the new road as soon as the bypasses were constructed, while Highway Beautification Act restrictions left existing properties with no means to obtain signage on the newly constructed Interstate. Some motels were demolished, converted to private residences, or used as storage space while others have been left to slowly fall apart.