North of Dumfries, SR 234 parallels Quantico Creek and follows the border of Prince William Forest Park to the southwest.

Just north of Lake Jackson, the state highway intersects Prince William Parkway (SR 294), which connects Manassas and Woodbridge.

SR 234 continues north past the Prince William Science and Technology Campus of George Mason University, which features the Hylton Performing Arts Center, then intersects SR 674 (Wellington Road) and Sudley Manor Drive, which connects Linton Hall to the southwest with Bull Run to the northeast.

After leaving the preserve, SR 234 passes through the community of Sudley Springs, where the highway crosses Little Bull Run and curves to the west.

[7] Also around that time, SR 234 was rerouted to head west rather than northwest from Catharpin, using a longer piece of new US 15 (from Woolsey north to Gilberts Corner).

[8] The piece at Bluemont was transferred to the secondary system in 1943,[9] truncating SR 234 back to Gilberts Corner and beyond to its current end at US 15.

[11] The Northern Virginia Transportation Alliance has recommended a new limited access highway extending SR 234 past its intersection with I-66.

[13][14] In March 2016, the Prince William County Board of Supervisors voted to remove the Bi-County Parkway from its long-range planning blueprint.

It would then follow SR 621 east of Manassas National Battlefield Park, ultimately connecting to Loudoun County Parkway.

The project would link Loudoun, Fairfax, and Prince William Counties and provide an alternate route between Manassas, I-66 and Washington Dulles International Airport.

[16] Some Prince William County supervisors support construction to extend Godwin Drive, as opposed to the Tri-County Parkway, due to the lower cost and lesser disruptive impact on residents and businesses.

[18] As a part of the Transform 66 project, the current at-grade intersection of SR 234 and Balls Ford Road will be converted to a diverging diamond interchange at a cost of $167 million.

As a part of this project, Balls Ford Road will be realigned about 0.50 miles (0.80 km) south, where the interchange will be constructed, and a new grade-separated bridge will be built over the Norfolk Southern Railroad Line.

Shortly after this point Grant Avenue reduces to two lanes, then divides into a boulevard with spaces for on-street parking, and passes by homes, some of which are antebellum in architecture.