A collector-distributor road runs parallel to the main travel lanes of a highway and connects it to frontage roads or entrance ramps. Collector-distributor roads are found at interchanges and allow motorists to bypass a traffic signal by driving under the intersecting road, much like an underpass.

Collector Distributor Roads illustration

Illustration: Collector-Distributor Roads

 

Collector Distributor Roads photo

Photograph: Collector-Distributor Roads

Source: The image above illustrates the key components of Collector-Distributor Roads.

 

A. Freeway mainlanes

B. Collector-Distributor road

C. Crossing road