Where are the lowest numbered East-West routes located?

The lowest numbered East-West routes are located in the southern part of the United States. This pattern is part of the U.S. Interstate Highway System, where the numbering convention for interstate highways follows a specific geography. Even-numbered highways are designated for East-West travel, and the numbers increase as you move further north. Specifically, highways like Interstate 10, which runs across the southern edge of the country, have lower numbers than those in the northern regions, such as Interstate 90. This system allows for easy navigation and understanding of regional travel patterns, showing how the layout of the highway system is organized geographically.