|The table below includes routes 200, 201, and 203, the precursors to the 500 system. 203 was designated on August 1, 1938, and the others (200 and 201) were probably designated at the same time. 202 was skipped because of US 202. The 200-series county routes were posted with state-style shields. In early February 1942, civil defense 5xx routes were established in New Jersey. For example, 501 paralleled US 1 and 532 was an extension of NY 32 into NJ. Some of these numbers (such as 501) survived onto their current routes. The image at left is a diagram from the New York Times. The civil defense system numbered these roadways as alternatives to state highways in case the latter needed to be co-opted for emergency defense/military use.|
|In 1952, the civil defense routes were changed to the current 5xx system, with the county name in a square shield. 500-series routes are now primary county highways, numbered by the state but routed and maintained by the counties. The 2xx system was removed soon after the 5xx system was adopted. The first version of these shields were still embossed, such as the 506 shield at right (taken by NJRoadfan) in Montclair, which stood into the new millennium but is now gone. Some counties continued to use the square shield longer than others; the shield at left (from Chris Mason) is somewhat newer, as it is not embossed. Bergen County still has many square route shields posted, though not new ones.|
New Jersey was one of the first states to adopt the standard county pentagon, though as I just mentioned, some counties took longer than others. The 505 photo, taken by SPUI, looks white but is faded yellow; some New Jersey counties put "___ COUNTY" in white with the number in yellow, while other counties put everything in white, but all yellow (as in the 579 photo taken by Ray Martin) is standard.|
Recently, many Spur and Alternate county routes were decommissioned, leaving only one case of duplication, the two Spur 549s. Other routes, including two Spur 527s (one intersected I-78 at Exit 36, the other intersected NJ 24 at Exit 8), are replaced by 600-series secondary county routes, or in the counties that didn't adopt the 600 numbering system, other non-500 county routes. Where possible, these decommissioned routes are included in the table below and on the route pages, but I know that SPUI and I are missing information on earlier routes.