East and Central Fairfax County

Accotink Creek crossing at the tripoint of Annandale, West Springfield, and North Springfield

SR 620 begins in Fairfax County at Columbia Pike (SR 244) near Lake Barcroft and runs southward, crossing the Little River Turnpike. It then intersects the Capital Beltway, Interstate 495. SR 620, heading westward at this point, then passes north of Burke and intersects SR 123 near George Mason University. It remains well south of Fairfax City and meets the freeway portion of Fairfax County Parkway. It then intersects SR 645 (Clifton Road) in Clifton, and next meets Union Mill Road. At this point, the road becomes New Braddock Road and SR 7783.^[1] New Braddock Road continues to SR 28.

In Centreville

While New Braddock Road continues straight, SR 620 itself is concurrent with SR 659 / Union Mill Road for one block. A new segment of Braddock Road (which shortly matches the old alignment of Braddock Road) starts here and heads west into Centreville. However, SR 620 quickly turns off onto a side-street, Spindle Court, and unceremoniously dead-ends behind Mountain View Alternative High School, creating another gap. The road that was SR 620 continues ahead as Old Braddock Road, SR 7759. Old Braddock Road continues ahead to Old Centreville Road (SR 898). That road connects to the beginning of the third segment of Braddock Road, which is located at a four-way intersection with US 29. This third segment was originally connected with what is now Spindle Court, but when a shopping center was built, a dead end on Braddock Road was created, and was renamed Spindle Ct. This segment only lasts for 0.32 mile, before turning into Pickwick Road (SR 1021).^[1]

Western Fairfax County

Braddock Road picks up again on the other side of I-66, at an intersection with SR 28. This fourth segment of SR 620 continues to the northwest, through several residential areas. It intersects with SR 609 (Pleasant Valley Road) and enters Loudoun County.

Loudoun County

Keeping the SR 620 designation, Braddock Road forms the southern border of South Riding where it intersects with and is the southern terminus of Loudoun County Parkway, SR 606. It then intersects with SR 659 (Gum Spring Road). It ends at the roundabout with SR 705 (Lightridge Farm Rd.) in Stone Ridge. Braddock Road, now designated SR 705, continues northwest to US 15 near Gilberts Corner.

Braddock Road where it forms the border of North Springfield

Among the cities, towns and other landmarks traversed by SR 620 are:

• the Thomas Jefferson High School for Science and Technology lies near the intersection with Little River Turnpike
• Annandale
• an intersection with the Capital Beltway
• Burke
• George Mason University
• Centreville
• Sully Station
• South Riding

Establishment, including pre-colonization era

Braddock Road was originally composed of paths established by the Native American inhabitants of Northern Virginia. Later, British colonialists and Virginian governments developed and improved the paths into what became known as "Braddock's Road."

Colonial and revolutionary era

Price's Common, a market that operated during the colonial administration and was the site of the drafting of the Virginia Declaration of Rights signed by George Mason (and after which the Bill of Rights of the United States Constitution was modeled), was located by the intersection of Braddock Road and Backlick Road.

Braddock Rd is so named as it was believed to be the route of the English General Edward Braddock's force during the French and Indian War. At the outset of the Braddock Expedition, the force was split into two groups. Braddock led the first group across the Potomac near Rock Creek and up to Frederick and Sir Peter Halkett led a second group through Northern Virginia. Halkett's group marched past the Old Fairfax County courthouse (today Tysons Corner) and up to Coleman's Ordinary (today Northern Herndon, Virginia). It is unlikely that today's Braddock Road was the actual route taken by Halkett's group. Rather, they roughly followed the route of present-day Leesburg Pike (Route 7).

Civil War

During the American Civil War, both Union and Confederate troops traversed Braddock Road during various battles in Fairfax County and other parts of Northern Virginia.

One of Mosby's Raiders, Robert Spindle, was a native of Centreville. Later, the part of SR 620 that was formed when Braddock Road was cut at US 29 was named after him, Spindle Court.^[7]

Modern era

With the advent of the modern road system, Braddock Road changed. In the 1930s after the Virginia Secondary Road system was created^[8] Braddock Road in Fairfax and Loudoun Counties was given the designation SR 620.

In the 1960s I-66 was built coming through Centreville.^[9] At this point the section of SR 620 between SR28 south of I-66 and a point north of the new I-66 was deleted, and a new SR 620 entrance was created intersecting with SR 28 north of I-66.

When SR 28 was widened from a 4-lane highway to a 6-lane one^[9] SR 620 was changed again. SR 620 south of I-66 no longer intersected with SR 28; SR 620 ended where Willoughby Newton Drive is now.

In the 1980s a shopping center was built at the corner of U.S. 29 and Old Centreville Road. At that time the non-SR 620 section of Braddock Road was constructed linking SR 620 to Old Centreville Road. The intersection between SR 620 and U.S. 29 was cut, and this small portion of SR 620 was renamed Spindle Court.^[9]

The Loudoun County Board of Supervisors undertook an effort in 1989 to give the county's roads names that were determined to be more historically accurate. The plan proposed to rename the county's portion of Braddock Road to Colchester Road, but this single change was removed immediately before adoption.^[10]

In the 1990s New Braddock Road was constructed linking Union Mill Road to SR 28. This is when SR 620 was cut, so that, on the east side of Union Mill Road, the road is Braddock Road, and on the west side it is New Braddock Road. Braddock Road heading west now intersects with Union Mill Road one block to the north.^[9]

The final change came in 2009. A barrier was erected on SR 28 that forced all traffic coming from SR 620 from the west to turn south on SR 28.

Fairfax County considered changing the intersection between SR 123 and SR 620 to a full interchange. The designs considered are diamond, a modified diamond interchange, an SPUI, and a tight SPUI.^[11] Ultimately, one left turn lane in each direction of SR 123 was added at the intersection, the left turn lane on eastbound SR 620 was extended, and new traffic signals were installed.^[12]