District of Columbia's at-large congressional district

The Yale Steam Laundry is a historic residence located on 437–443 New York Avenue, Northwest, Washington, D.C., in the Mount Vernon Square neighborhood.

This list of tallest buildings in Washington, D.C. ranks high-rises in the U.S. capital of Washington, D.C. The tallest structure in the city, excluding radio towers, is the Washington Monument, which rises 555 feet (169 m) and was completed in 1884. The structure, however, is not generally considered a high-rise building as it does not have successive floors that can be occupied. The tallest habitable building in the city is the Basilica of the National Shrine of the Immaculate Conception, which rises 329 feet (100 m). The second-tallest building in Washington is the Old Post Office Building, which is 315 feet (96 m) high. The third-tallest building in the city is the Washington National Cathedral, which rises 301 feet (92 m) above grade. The cathedral is built on high ground known as Mount St. Alban, 400 feet (120 m) above sea level, which makes the central tower the "highest" point in the District. As of November 2011, there are 410 completed high-rises in the city.

Washington, D.C., formally the District of Columbia, also known as just Washington or simply D.C., is the capital city and only federal district of the United States. It is located on the east bank of the Potomac River, which forms its southwestern and southern border with the U.S. state of Virginia, and shares a land border with the U.S. state of Maryland on its remaining sides. The city was named for George Washington, a Founding Father and the first president of the United States, and the federal district is named after Columbia, a female personification of the nation. As the seat of the U.S. federal government and several international organizations, the city is an important world political capital. It is one of the most visited cities in the U.S., seeing over 20 million visitors in 2016.The U.S. Constitution provides for a federal district under the exclusive jurisdiction of Congress; the district is therefore not a part of any U.S. state (nor is it one itself). The signing of the Residence Act on July 16, 1790, approved the creation of a capital district located along the Potomac River near the country's East Coast. The City of Washington was founded in 1791 to serve as the national capital, and Congress held its first session there in 1800. In 1801, the territory, formerly part of Maryland and Virginia (including the settlements of Georgetown and Alexandria), officially became recognized as the federal district. In 1846, Congress returned the land originally ceded by Virginia, including the city of Alexandria; in 1871, it created a single municipal government for the remaining portion of the district. There have been efforts to make the city into a state since the 1880s, a movement that has gained momentum in recent years, and a statehood bill passed the House of Representatives in 2021.The city is divided into quadrants centered on the Capitol Building, and there are as many as 131 neighborhoods. According to the 2020 Census, it has a population of 689,545, which makes it the 20th-most populous city in the U.S., third-most populous city in both the Mid-Atlantic and Southeast, and gives it a population larger than that of two U.S. states: Wyoming and Vermont. Commuters from the surrounding Maryland and Virginia suburbs raise the city's daytime population to more than one million during the workweek. Washington's metropolitan area, the country's sixth-largest (including parts of Maryland, Virginia and West Virginia), had a 2019 estimated population of 6.3 million residents.The three branches of the U.S. federal government are centered in the district: Congress (legislative), the president (executive), and the Supreme Court (judicial). Washington is home to many national monuments and museums, primarily situated on or around the National Mall. The city hosts 177 foreign embassies as well as the headquarters of many international organizations, trade unions, non-profits, lobbying groups, and professional associations, including the World Bank Group, the International Monetary Fund, the Organization of American States, the AARP, the National Geographic Society, the Human Rights Campaign, the International Finance Corporation, and the American Red Cross. A locally elected mayor and a 13-member council have governed the district since 1973. Congress maintains supreme authority over the city and may overturn local laws. D.C. residents elect a non-voting, at-large congressional delegate to the House of Representatives, but the district has no representation in the Senate. District voters choose three presidential electors in accordance with the Twenty-third Amendment to the United States Constitution, ratified in 1961.

The Government of the District of Columbia operates under Article One of the United States Constitution and the District of Columbia Home Rule Act, which devolves certain powers of the United States Congress to the Mayor and thirteen-member Council. However, Congress retains the right to review and overturn laws created by the council and intervene in local affairs.

Lead contamination in Washington, D.C., drinking water, first discovered in 2001, left thousands of children with lifelong health risks, and led to a re-evaluation of the use of monochloramine in public drinking-water systems. Professor Marc Edwards, an expert in plumbing corrosion, discovered lead levels at least 83 times higher than the accepted safe limit while performing research into premature pipe corrosion for the District of Columbia Water and Sewer Authority (WASA). He found that the decision to change from chlorine to chloramine as a treatment chemical had caused the spike in lead levels. After the Washington Post ran a series of front-page articles about Edwards's findings, resulting in widespread public concern, the United States House of Representatives conducted an investigation. The House found that the U.S. Centers for Disease Control and Prevention (CDC) had made "scientifically indefensible" claims in a report that had indicated there was no risk from the high lead levels. The Post investigation uncovered evidence of widespread misreporting of lead levels at water agencies across the United States, leading to regulatory crackdowns and changes in Environmental Protection Agency policies. The problem was addressed in 2004 by adding additional treatments to the water, preventing the chloramine from dissolving lead in the water mains, solder joints, and plumbing fixtures. In 2010, the CDC reported that 15,000 homes in the Washington, D.C., area might still have water supplies with dangerous levels of lead.

Fletcher Chapel, also known as Church of God and the Saints of Christ Church, is a historic chapel located in Northwest, Washington, D.C. It was built in 1854 by the McKendree Methodist Episcopal Church to start a new congregation known as Fletcher Chapel Methodist Episcopal Church. The building was purchased by the Church of God and the Saints of Christ Church in 1904 and added to the National Register of Historic Places in 1997.

Rigo Walled Park is a neighborhood-named urban open space located on National Park Service property south of New York Avenue at L Street, NW in the Mount Vernon Square neighborhood of Washington, D.C. It is administered as part of the National Mall and Memorial Parks.

Mount Vernon Triangle is a neighborhood and community improvement district in the northwest quadrant of Washington, D.C. Originally a working-class neighborhood established in the 19th century, present-day Mount Vernon Triangle experienced a decline in the mid-20th century as it transitioned from residential to commercial and industrial use. The neighborhood has undergone significant and rapid redevelopment in the 21st century. It now consists mostly of high-rise condominium, apartment and office buildings. Several historic buildings in the neighborhood have been preserved and are listed on the National Register of Historic Places. Mount Vernon Triangle is now considered a good example of urban planning and a walkable neighborhood.

The Northern Liberty Market, later called Convention Hall Market and Center Market, was located on the east side of 5th Street NW, between K and L, in the present-day Mount Vernon Triangle neighborhood of Washington, D.C. It operated from 1875 to 1963.

Second Baptist Church is a historic church located at 816 3rd Street NW in the Mount Vernon Triangle neighborhood of Washington, D.C. It was built in 1894 and designed by Appleton P. Clark, Jr. It was added to the National Register of Historic Places in 2004.

dLeña is a Latin American / Mexican restaurant in Mount Vernon Triangle, Washington, D.C.

The Mount Vernon Triangle Historic District is a historic district in the Mount Vernon Triangle neighborhood of Washington, D.C., consisting of 22 contributing residential, commercial, and industrial buildings, and one known archaeological site. The area was once a working class neighborhood for mostly German immigrants and home to semi-industrial enterprises such as a dairy and an automobile repair shop. The Northern Liberty Market that once stood on the corner of 5th Street and K Street NW played a large role in spurring development in the surrounding area as did the streetcars on Massachusetts Avenue and New York Avenue. The historic district was added to the District of Columbia Inventory of Historic Sites in 2005 and the National Register of Historic Places in 2006. The 22 buildings in the district were constructed between 1869 and 1946. Two of the buildings included in the historic designation process, 470 and 472 K Street NW, collapsed in 2014. Many of the buildings in the district have undergone a restoration process. Prather's Alley, which was once lined with dwellings, stables, and industrial businesses, is being redeveloped into a place for community residents to gather.