Numbered Highways in San Andreas (often called routes or highways) is a system of inter-connecting roads and highways that criss-cross the HD-Era State of San Andreas. Routes usually consist of only two lane roads with multi-lane roads and freeways in some sections. Grand Theft Auto V has the most realistic and extensive freeway system of any other GTA game to date.
The system is based on the real-life numbering system in the United States, but with some differences. Rural major routes (such as Routes 1 and 13) are signed with U.S. Route shields, while minor urban routes (such as Routes 14 and 17) are marked on freeway guide signs with generic state highway markers. The Interstate System almost always consists of multi-lane freeways and are usually traveled on more than the Routes.