1927 New Jersey state highway renumbering

In 1927, New Jersey's state highways were renumbered. The old system, which had been defined in sequence by the legislature, was growing badly, as several routes shared the same number, and many unnumbered state highways had been defined. A partial renumbering was proposed in 1926, getting rid of the duplicates and assigning numbers to many of the unnumbered routes, but instead a total renumbering was done in 1927.

Chapter 319 of the 1927 public laws defined the new system of routes. Major roads received numbers from 1 to 12 and 21 to 50, as follows:

Spurs were also defined, being assigned a prefix of S. For example, Route S26 was a short spur of Route 26 connecting to Route 25 south of New Brunswick. A second spur of Route 4 was assigned Route S4A, but two separate spurs of Route 24 both received the Route S24 designation.

While the majority of already-acquired routes were included in the new system, four sections of pre-1927 routes were not. The law authorizing the renumbering indicated that these were to remain, and so the State Highway Commission added a suffix of N to distinguish them from the new routes of the same number:

Some amendments were made in 1929, including the elimination of Route 18N (by merging it into Route 1), and the addition of more spurs, as well as Route 29A, but the system stayed mostly intact until the 1953 renumbering.

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