In the U.S. state of New Jersey, county routes exist in all 21 counties. They are typically the fourth type of roadway classified below the Interstate Highway, the U.S. Route numbered highway and the state highway. The County Route system is defined by two types in New Jersey. First, 500 Series County Routes, also called state secondary routes (to the state highway), are county highways numbered in a statewide system with three-digit numbers that begin with 5. These roads form a second network of routes that supplement the facilitation of the State Routes. Each 500 Series route is unique and is not permitted to be duplicated in another county for a separate route. The second category is defined as Non-500 Series County Routes. Non-500 Series County Routes include 1-digit, 2-digit, 600 Seri