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.
List of Interstate Highways in Georgia (U.S. state)
The Interstate Highways in Georgia comprise seven current primary Interstate Highways and eight auxiliary Interstates. In addition, two primary Interstates are currently under proposal, and three auxiliary Interstates were once proposed and than cancelled. Each Interstate has a hidden state route number; for example, Interstate 75 (I-75) is also State Route 401 (SR 401) and Interstate 16 (I-16) is also State Route 404 (SR 404, the Jim Gillis Historic Savannah Parkway). This highway system uses the Georgia Peach Pass for toll lanes.