A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic entering and exiting the highway via ramps. A controlled-access highway provides an unhindered flow of traffic, with no traffic signals, intersections or property access. They are free of at-grade intersections with other roads, railways, bicycle lanes or pedestrian paths, which are instead carried by overpasses and underpasses. Interchanges also allow access to and from other major highways, frontage roads, arterials and collectors.

Controlled Access illustration

Illustration: Controlled Access

 

Controlled Access photo

Photograph: Controlled Access

A. Controlled-Access Fully Direction Interchange without Frontage Roads