Narrow gauge railway at Camp A. A. Humphreys

Fort Belvoir is a United States Army installation and a census-designated place (CDP) in Fairfax County, Virginia, United States. It was developed on the site of the former Belvoir plantation, seat of the prominent Fairfax family for whom Fairfax County was named. It was known as Camp A. A. Humphreys from 1917 to 1935 and Fort Belvoir afterward. Fort Belvoir is home to a number of significant United States military organizations. With nearly twice as many workers as The Pentagon, Fort Belvoir is the largest employer in Fairfax County. Fort Belvoir comprises three geographically distinct areas: main base, Davison Army Airfield, and Fort Belvoir North.

The Defense Contract Audit Agency (DCAA) is an agency of the United States Department of Defense under the direction of the Under Secretary of Defense (Comptroller). It was established in 1965 to perform all contract audits for the Department of Defense. Previously, the various branches of military service were responsible for their own contract audits. The DCAA's duties include financial and accounting advisory services for the Department of Defense in connection with negotiation, administration and settlement of contracts and subcontracts.

The Defense Threat Reduction Agency (DTRA) is both a defense agency and a combat support agency within the United States Department of Defense (DoD) for countering weapons of mass destruction (WMD; chemical, biological, radiological, nuclear, and high explosives) and supporting the nuclear enterprise. According to the agency's website its mission states that "DTRA provides cross-cutting solutions to enable the Department of Defense, the United States Government, and international partners to Deter strategic attack against the United States and its allies; Prevent, reduce, and counter WMD and emerging threats; and Prevail against WMD-armed adversaries in crisis and conflict." The agency is headquartered in Fort Belvoir, Virginia.

The Center for Army Analysis (CAA), formerly US Army's Center for Strategy and Force Evaluation, is a US Army organization under the Deputy Chief of Staff G-8 (DCS G-8) which is responsible for analyses that impact the Army at the strategic or institutional level.

Accotink is an unincorporated community in Fairfax County, Virginia, United States. Accotink is located along Accotink Creek within Fort Belvoir.

The Woodlawn Quaker Meetinghouse is located at 8890 Woodlawn Road in Alexandria, Virginia, United States. The meetinghouse and its associated cemetery are significant for their role in the Quaker community in this area of Virginia in the mid to late 19th century. The meetinghouse itself is also significant for its Quaker Plain Style architecture. The property was added to the National Register of Historic Places on May 21, 2009, and the listing was announced as the featured listing in the National Park Service's weekly list of May 29, 2009.The original meetinghouse, now the southern half, was built in 1853. The northern half was added between 1866 and 1869. Both halves are wood frame, one story, gable roofed structures. The style reflects the Quaker belief in simplicity and lack of adornment. The rectangular building faces east, with two entrances on the long side of the rectangle. One entrance was for women, and one for men. On the interior, there is a center wall with window-like opening. The openings can be shuttered to accommodate separate meetings for men and women. The seating is historic, simple, wooden benches. The porch that currently wraps around the building was added at a later time. Union soldiers occupied the building during the American Civil War, and carved their names and initials to the right of what was then the only entryway.

Humphreys National Forest was established in Virginia by the U.S. Forest Service on April 10, 1925 with 3,184 acres (12.89 km2) from part of the Humphreys Military Reservation, now Fort Belvoir. On April 11, 1928 the executive order for its creation was rescinded and the forest was abolished.

The National Museum of the United States Army is the official museum for the history of the United States Army and is just outside Washington, D.C. It opened on November 11, 2020. The objectives of the museum are to honor America's soldiers, preserve Army history, and educate the public about the Army's role in American history. The U.S. Army announced April 16, 2020 that the museum would delay its opening due to the COVID-19 pandemic.The National Museum is located on 84 acres at Fort Belvoir, Virginia, 20 miles south of Washington, D.C. Ground was broken for the museum in September 2016, and it was scheduled to open on June 4, 2020. That opening was delayed as some of the gallery finishing work was suspended in response to COVID-19 which impacted the project timeline. The main building is approximately 185,000 square feet and displays selections from the United States Army Center of Military History. Outside this facility is a park with gardens and a parade ground. Space is included to accommodate ceremonies, reenactments, lectures, educational programs, and reunions.

Aerospace Data Facility-East (ADF-E), also known as Area 58 and formerly known as Defense Communications Electronics Evaluation and Testing Activity (DCEETA), is one of three satellite ground stations operated by the National Reconnaissance Office (NRO) in the continental United States. Located within Fort Belvoir, Virginia, the facility is responsible for the command and control of reconnaissance satellites involved in the collection of intelligence information and for the dissemination of that intelligence to other U.S. government agencies.

The Pope–Leighey House, formerly known as the Loren Pope Residence, is a suburban home in Virginia designed by American architect Frank Lloyd Wright. The house, which belongs to the National Trust for Historic Preservation, has been relocated twice and sits on the grounds of Woodlawn Plantation, Alexandria, Virginia. Along with the Andrew B. Cooke House and the Luis Marden House, it is one of the three homes in Virginia designed by Wright.

The Institute of Heraldry, officially The Institute of Heraldry, Department of the Army, is an activity of the Administrative Assistant to the Secretary of the Army solely responsible for furnishing heraldic services to the President of the United States and all Federal Government agencies. Title 18 of the United States Code, Chapter 33, Section 704 and Title 32 of the Code of Federal Regulations, Part 507 permit the institute to issue directives on how military insignia are displayed, the criteria for issuance, and how insignia will be worn on military uniforms. The activities of The Institute of Heraldry encompass research, design, development, standardization, quality control, and other services relating to official symbolic items—seals, decorations, medals, insignia, badges, flags, and other items awarded to or authorized for official wear or display by federal government personnel and agencies. Limited research and information services concerning official symbolic items are also provided to the general public. The Institute of Heraldry is located at 9325 Gunston Road, Fort Belvoir, Virginia, a military installation in the U.S. Army Military District of Washington. The institute employs 22 Department of the Army civilians.

Woodlawn is a historic house located in Fairfax County, Virginia. Originally a part of Mount Vernon, George Washington's historic plantation estate, it was subdivided in the 19th century by abolitionists to demonstrate the viability of a free labor system. The address is now 9000 Richmond Highway, Alexandria, Virginia, but due to expansion of Fort Belvoir and reconstruction of historic Route 1, access is via Woodlawn Road slightly south of Jeff Todd Way/State Route 235. The house is a designated National Historic Landmark, primarily for its association with the Washington family, but also for the role it played in the historic preservation movement. It is now a museum property owned and managed by the National Trust for Historic Preservation.