Question: Dar Al-Hijrah is a mosque in what county near the United States capital?

Context paragraphs:
National Museum of African Art: The National Museum of African Art is the Smithsonian Institution's African art museum, located on the National Mall of the United States capital.  Its collections include 9,000 works of traditional and contemporary African art from both Sub-Saharan and Arab North Africa, 300,000 photographs, and 50,000 library volumes.  It was the first institution dedicated to African art in the United States, and remains the largest collection. " The Washington Post" called the museum a mainstay in the international art world and the main venue for contemporary African art in the United States.

Washington metropolitan area: The Washington metropolitan area is the metropolitan area centered on Washington, D.C., the capital of the United States.  The area includes all of the federal district and parts of the U.S. states of Maryland and Virginia, along with a small portion of West Virginia.

M Street (Washington, D.C.): The name "M Street" refers to two major roads in the United States capital of Washington, D.C. Because of the Cartesian coordinate system used to name streets in Washington, the name "M Street" can be used to refer to any east-west street located twelve blocks north or south of the dome of the United States Capitol (not thirteen blocks, as there is no J Street).  Thus, in all four quadrants of the city there are streets called "M Street", which are disambiguated by quadrant designations, namely, M Street NW NE, SW, and SE.

2017 al-Jinah airstrike: On 16 March 2017, an airstrike by the United States Armed Forces killed up to 49 people in the rebel-held village of al-Jinah near Aleppo, Syria.  The US military claimed the people targeted were militants belonging to the terrorist group al-Qaeda.  However, the Syrian Observatory for Human Rights (SOHR), local residents and local officials have claimed that the building struck was a mosque filled with worshipers.  At the time, US military claimed that the structure bombed was not a mosque itself but was next to a mosque, which was undamaged.  However, on May 5, 2017, a US Central Command investigation determined that the building was indeed part of a mosque-complex.  Rami Abdel Rahman, head of SOHR, claimed the structure was a mosque which held over 300 people at the time of the strike.

Bois Brule River: The Bois Brule River (most often referred to as the Brule River) is located in Douglas County, Wisconsin, United States, near the county's eastern border with Bayfield County.  The river is 43.9 mi long.  The source is in central Douglas County near Upper St. Croix Lake, it flows through the Brule River State Forest, and drains into Lake Superior.

Texas's 27th congressional district: Texas District 27 of the United States House of Representatives is a Congressional district that serves the coastal bend of Texas' Gulf Coast consisting of Corpus Christi and Victoria up to Bastrop County near Austin and Wharton County near Houston.  The current Representative is Republican Blake Farenthold.

Dar Al-Hijrah: The Dar Al-Hijrah Islamic Center (Arabic: مركز دار الهجرة الاسلامي‎ ‎ , English: Land of Migration ) is an open mosque in Northern Virginia.  It is located in the Seven Corners area of unincorporated Fairfax County, Virginia in the Washington, D.C. metropolitan area.

Height of Buildings Act of 1910: The Height of Buildings Act of 1910 was an Act of Congress passed by the 61st United States Congress on June 1, 1910 to limit the height of buildings in Washington, D.C. The original act was passed on March 1, 1899 when the 55th United States Congress approved the Height of Buildings Act of 1899.  The original act restricted the heights of any type of building in the United States capital city of Washington, D.C., to be no higher than 110 ft .  In 1910, the 61st United States Congress enacted a new height restriction law limiting building heights to 130 ft , or the width of the right-of-way of the street or avenue on which a building fronts, whichever is shorter.  That is the main law presented by this act.

Organization of American States: The Organization of American States (Spanish: "Organización de los Estados Americanos" , Portuguese: "Organização dos Estados Americanos" , French: "Organisation des États américains" ), or the OAS or OEA, is a continental organization founded on 30 April 1948, for the purposes of regional solidarity and cooperation among its member states.  Headquartered in the United States capital Washington, D.C., the OAS's members are the 35 independent states of the Americas.

Divide, Oregon: Divide is a ghost town in Lane County, Oregon, United States, located southwest of Cottage Grove, near Interstate 5.  A post office in Douglas County near a train station on the Southern Pacific Railroad was established on May 31, 1900, and it was closed on January 15, 1921.  In 1909, the post office was relisted as a Lane County post office.  It may have been moved across county borders, or its county may have changed during a shift in the border between Lane and Douglas counties.

Supporting paragraphs: Dar Al-Hijrah Washington metropolitan area
Answer: Fairfax County