In which direction do even-numbered interstates generally run?

Even-numbered interstates are designed to facilitate east-west travel across the United States. The numbering system employed by the Interstate Highway System assigns even numbers to routes that run horizontally, reflecting geographic direction. The lower numbers, such as Interstate 10, typically traverse the southern part of the country, while the higher numbers, like Interstate 90, are found further north. This standardized approach helps drivers easily identify the direction of travel associated with specific interstate numbers, enhancing navigation and route planning.

In contrast, odd-numbered interstates are assigned for north-south travel, offering a clear way to distinguish between the two types of routes based on their numbering system. The diagonal and specific directional options such as southwest to northeast do not apply to even-numbered interstates, which consistently align with east-west travel.