A prime meridian is an arbitrary meridian in a geographic coordinate system at which longitude is defined to be 0°. Together, a prime meridian and its anti-meridian form a great circle. This great circle divides a spheroid, like Earth, into two hemispheres: the Eastern Hemisphere and the Western Hemisphere. For Earth's prime meridian, various conventions have been used or advocated in different regions throughout history. Earth's current international standard prime meridian is the IERS Reference Meridian. It is derived, but differs slightly, from the Greenwich Meridian, the previous standard.
The National Mall is a landscaped park near the downtown area of Washington, D.C., the capital city of the United States. It contains and borders a number of museums of the Smithsonian Institution, art galleries, cultural institutions, and various memorials, sculptures, and statues. It is administered by the National Park Service (NPS) of the United States Department of the Interior as part of the National Mall and Memorial Parks unit of the National Park System. The park receives approximately 24 million visitors each year.
Pierre "Peter" Charles L'Enfant was an American-French military engineer who in 1791 designed the basic plan for Washington, D.C., the capital city of the United States. His work is known today as the L'Enfant Plan. He also inspired the street plan for Detroit, Michigan.
McPherson Square station is a Washington Metro station in Downtown, Washington, D.C., United States. The side-platformed station is operated by the Washington Metropolitan Area Transit Authority (WMATA). Providing service for the Blue, Orange, and Silver Lines, the station is located between McPherson Square and Franklin Square, with two entrances on I Street at Vermont Avenue and 14th Street NW. This is the main station to access the White House, and the Vermont Avenue exit is directly underneath the Department of Veterans Affairs building.
Smithsonian station is a Washington Metro station at the National Mall in Washington, D.C., United States. The side platformed station was opened on July 1, 1977, and is operated by the Washington Metropolitan Area Transit Authority (WMATA). It is a stop on the Blue, Orange and Silver Lines. The station's south entrance is at the southwest corner of Independence Avenue and 12th Street, Southwest, the street elevator is at the northwest corner of the same intersection, and the north entrance is on the south side of the Mall near Jefferson Drive, Southwest.
The Zero Milestone is a zero mile marker monument in Washington, D.C., intended as the initial milestone from which all road distances in the United States should be measured when it was built. At present, only roads in the Washington, D.C., area have distances measured from it.
The history of Washington, D.C., is tied to its role as the capital of the United States. The site of the District of Columbia along the Potomac River was first selected by President George Washington. The city came under attack during the War of 1812 in an episode known as the Burning of Washington. Upon the government's return to the capital, it had to manage the reconstruction of numerous public buildings, including the White House and the United States Capitol. The McMillan Plan of 1901 helped restore and beautify the downtown core area, including establishing the National Mall, along with numerous monuments and museums.
Massachusetts Avenue is a major diagonal transverse road in Washington, D.C., and the Massachusetts Avenue Historic District is a historic district that includes part of it.
16th Street Northwest, briefly known as the Avenue of the Presidents, is a prominent north-south boulevard in Washington, D.C., located in Northwest D.C. The street was laid out as part of the 1791 L'Enfant Plan, which served as the original blueprint for the city. The street begins just north of the White House, across from Lafayette Square in the President's Park, and continues north along the Washington meridian until Blair Circle.
Freedom Plaza, originally known as Western Plaza, is an open plaza in Northwest Washington, D.C., United States, located near 14th Street and Pennsylvania Avenue NW, adjacent to Pershing Park. The plaza features an inlay that partially depicts Pierre (Peter) Charles L'Enfant's plan for the City of Washington. The National Park Service administers the Plaza as part of its Pennsylvania Avenue National Historic Site and coordinates the Plaza's activities.
Andrew Ellicott was an American land surveyor who helped map many of the territories west of the Appalachians, surveyed the boundaries of the District of Columbia, continued and completed Pierre (Peter) Charles L'Enfant's work on the plan for Washington, D.C., and served as a teacher in survey methods for Meriwether Lewis.
The Ellipse, sometimes referred to as President's Park South, is a 52-acre (21 ha) park south of the White House fence and north of Constitution Avenue and the National Mall in Washington, D.C., US. The Ellipse is also the name of the five-furlong (1.0 km) circumference street within the park. The entire park, which features monuments, is open to the public and is part of President's Park. The Ellipse is the location for many annual events.
Scott Circle is an area in the northwest quadrant of Washington, D.C. that is centred on the junction of Massachusetts Avenue, Rhode Island Avenue, and 16th Street, N.W. Originally a neighborhood recreational area like nearby Dupont Circle, Scott has lost all social uses except as the location for public memorials.
Jefferson Pier, Jefferson Stone, or the Jefferson Pier Stone, in Washington, D.C., marks the second prime meridian of the United States even though it was never officially recognized, either by presidential proclamation or by a resolution or act of Congress.
Tiber Creek or Tyber Creek, originally named Goose Creek, is a tributary of the Potomac River in Washington, D.C. It was a free-flowing creek until 1815, when it was channeled to become part of the Washington City Canal. Presently, it flows under the city in tunnels, including under Constitution Avenue NW.
The Washington City Canal operated from 1815 until the mid-1850s in Washington, D.C. The canal connected the Anacostia River, termed the "Eastern Branch" at that time, to Tiber Creek, the Potomac River, and later the Chesapeake and Ohio (C&O) Canal. The canal became disused during the late 19th century and the city government covered over or filled in various sections in 1871.
The boundary markers of the original District of Columbia are the 40 milestones that marked the four lines forming the boundaries between the states of Maryland and Virginia and the square of 100 square miles (259 km2) of federal territory that became the District of Columbia in 1801. Working under the supervision of three commissioners that President George Washington had appointed in 1790 in accordance with the federal Residence Act, a surveying team led by Major Andrew Ellicott placed these markers in 1791 and 1792. Among Ellicott's assistants were his brothers Joseph and Benjamin Ellicott, Isaac Roberdeau, George Fenwick, Isaac Briggs and an African American astronomer, Benjamin Banneker.
The German-American Friendship Garden on the National Mall in Washington, D.C. stands as a symbol of the positive and cooperative relations between the United States of America and the Federal Republic of Germany.
The L'Enfant Plan for the city of Washington is the urban plan developed in 1791 by Major Pierre Charles L'Enfant for George Washington, the first president of the United States.
The Garden Club of America Entrance Markers in Washington, D.C., are carven stone pylons installed along the border of the District of Columbia in 1932 and 1933 by local Garden Club of America chapters. Originally about five feet tall, the markers were placed at important entrance points to the national capital. Seven survive: sets of two markers in Westmoreland Circle, Friendship Heights, and Chevy Chase Circle; and a single marker along Georgia Avenue. These surviving markers are listed on the National Register of Historic Places.
