Route 10 is a state highway in the northern part of the U.S. state of New Jersey. It runs from an intersection of U.S. Route 46 in Roxbury, Morris County, east to Prospect Avenue / Mount Pleasant Avenue (CR 577 / CR 677) in West Orange, Essex County. Route 10 is a major route through northern New Jersey that runs through Ledgewood, East Hanover Township, and Livingston. It is a four-lane highway for most of its length with the exception of the easternmost part of the route. Route 10 features intersections and interchanges with many major roads including Route 53 and U.S. Route 202 in Morris Plains and Interstate 287 in Hanover Township.
Route 10 was designated in 1927 to run from Jersey City to Dover, following the former Newark and Mount Pleasant Turnpike west of Newark. The route continued east from its present-day routing on current County Route 577, Park Avenue, CR 508, and Route 7 to end at U.S. Route 1/9 at the Tonnele Circle. An alignment of Route 10 farther to the north of its current alignment in Essex County was proposed in 1952; however, it was never constructed with the route being designated to its present alignment a year later. Since 1953, Route 10 has seen improvements that eliminated the Ledgewood Circle at the western terminus in 1998 and improved safety along the portion of the route in Hanover and East Hanover townships in the mid-2000s.
Route description
thumb|left|Route 10 eastbound past its western terminus at U.S. Route 46 in Roxbury TownshipRoute 10 begins at the intersection of US 46 in the Ledgewood section of Roxbury, Morris County at the former Ledgewood Circle, heading to the southeast on a four-lane divided highway with some jughandles. The route crosses the Dover & Rockaway River Railroad's Chester Branch before it enters Randolph, where the road becomes less commercial in nature and passes Randolph Lake, reaching an interchange of Sussex Turnpike (CR 617). Past this interchange, Route 10 crosses over forested Mine Hill. The Newark and Mount Pleasant Turnpike was established along the present-day alignment of Route 10 east of Dover on March 12, 1806, existing as a turnpike until before 1833.
thumb|left|View eastbound along Route 10 from County Route 665 in Randolph
Route 10 was designated in 1927 to run from Jersey City west to Route 6 (now US 46) west of Dover, passing through Newark. This routing of Route 10 followed its current alignment and ran east along present-day CR 577, Mt Pleasant Avenue, and Park Avenue to Newark, where it followed CR 508 and Route 7 to US 1/9 at the Tonnele Circle in Jersey City. By 1930, the road's western terminus had been moved to bypass Dover to terminate at Ledgewood. The earliest completed sections of an upgraded highway were completed from Livingston Circle to Whippany, with the bridge over the Passaic River completed in 1930. From there the road was extended to Route 53 and finished at Ledgewood. In Essex County, the route that the highway would be constructed along was contentious from the start. In 1930 and 1931, three proposals for arteries were presented, all paralleling existing railroads. Though demands to decide a route and begin construction extended to at least 1937, no highway was ever constructed, and the road terminated at West Orange.
To solve this issue, a new route for Route 10 was designated in 1952 to run along a new, never-built alignment farther to the north, running through Belleville, Bloomfield, Glen Ridge, Montclair, West Orange, and along the Livingston/Roseland border, roughly along much of the routing of present-day CR 611 (Eagle Rock Avenue), and following its current alignment through Morris County to Ledgewood. A spur of the route was also planned in 1952 to run from Montclair south to Orange. A year later, in the 1953 New Jersey state highway renumbering, Route 10 was defined onto its current alignment, with its eastern terminus moved to Prospect Avenue in West Orange. In 1998, the Ledgewood Circle at the western terminus of the route was replaced with a signalized T-intersection. In the mid-2000s, an $11.5 million project was undertaken to improve safety on the portion of Route 10 in Hanover and East Hanover Townships by widening existing lanes and adding turning lanes to the road.
Joint Resolution No. 3, page 844, of the 160th Legislature (1936) designated Route 10 as the American Legion Memorial Highway in honor of the services of the members of the American Legion in World War I.