Route 34 is a state highway in the central part of the U.S. state of New Jersey. The route runs from an intersection with Route 35 and Route 70 (the former Brielle Circle) in Wall Township, Monmouth County, north to an interchange with U.S. Route 9 (US 9) in Old Bridge Township, Middlesex County. The route is a four-lane divided highway between its southern terminus and the north end of the Route 33 concurrency in Howell Township; along this stretch, the route intersects the Garden State Parkway and Interstate 195 (I-195)/Route 138 within a short distance of each other. North of Route 33, Route 34 is an undivided two- to four-lane road that intersects Route 18 in Colts Neck Township and Route 79 in Matawan. Route 34 passes through mostly suburban areas along its route.
The route was legislated in 1927 to run from Route 35 (present Route 88) in Laurelton north to Route 4 (present Route 79) in Matawan. The current alignment of Route 34 north of Matawan was a part of Route 4 (and later US 9) until it became a part of Route 4A following a realignment of US 9 and Route 4. In 1953, Route 34 was extended north along Route 4A to end at US 9 in Old Bridge Township. Meanwhile, the southern terminus was cut back to its current location with the route south of that point becoming a part of Route 70. Since 1953, the southern portion of the route was widened into a divided highway and the Brielle Circle was replaced.
Route description
thumb|left|Route 34 northbound just north of Route 35 and Route 70.
Route 34 begins at an intersection with Route 35 and Route 70 in Wall Township, Monmouth County, at the former Brielle Circle, heading to the northwest on a six-lane undivided road. Past the Allenwood Circle, the road continues northwest to a partial interchange with the Garden State Parkway. This interchange has access to the northbound Garden State Parkway from northbound Route 34, to the southbound Garden State Parkway from southbound Route 34, and to both directions of Route 34 from the southbound Garden State Parkway. and ran between Holmdel Township and Middletown Point (now Matawan). The road's trajectory is now roughly followed by Route 34.
In the 1927 New Jersey state highway renumbering, Route 34 was legislated to run from an intersection with Route 35 (now Route 88 in Laurelton, Ocean County, north to Route 4 (now Route 79) in Matawan, with the portion of current Route 34 north of that intersection legislated as part of Route 4. By the 1940s, US 9 was also designated along the present-day portion of Route 34 that was then a part of Route 4, this would later become Route 4A after US 9 and Route 4 were moved to a new alignment between Freehold and Cheesequake. In the 1953 New Jersey state highway renumbering, Route 34 was extended north along the alignment of Route 4A to end at US 9 in Cheesequake while the southern terminus was cut back to the Brielle Circle intersection with Route 35 and Route 70, the latter having replaced Route 34 south of this point. By 1969, Route 34 was widened into a divided highway as far north as Route 33. The Brielle Circle at the southern terminus of the route was converted into at-grade intersections with traffic lights in 2001.