Second Division Memorial

On November 11, 2011, Oscar Ramiro Ortega-Hernandez, an unemployed 21-year-old man, fired multiple shots at the White House using a semi-automatic rifle. At least seven bullets hit the second floor. Neither the President Barack Obama nor First Lady Michelle Obama were home at the time; the president was not in Washington, D.C., having been on a trip abroad. However, the couple's youngest daughter, Sasha, and the first lady's mother, Marian Shields Robinson, were in the White House. No one was injured. It took four days for the Secret Service to realize that bullets had struck the White House. Michelle Obama learned of the shooting from an usher, then summoned Mark J. Sullivan, director of the Secret Service, to find out why the first family had not been informed. In September 2013, Ortega-Hernandez pleaded guilty to one count of property destruction and one count of discharging a firearm during a crime of violence, thereby avoiding being charged with an attempt to assassinate the President. In March 2014, he was sentenced to 25 years' imprisonment. In September 2014, The Washington Post published an investigative report detailing errors that the Secret Service made on the night of the shooting that led to the crime going undiscovered. A House of Representatives hearing followed and Julia Pierson, director of the Secret Service, resigned the following week. It was the first shooting at the White House since Francisco Martin Duran's attempted assassination of President Bill Clinton in 1994.

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. Situated within the Washington Monument grounds on the historic axis between the Jefferson Pier and the White House (see White House meridian), the garden borders Constitution Avenue Northwest between 15th and 17th Streets Northwest, where an estimated seven million visitors pass each year. The garden features plants native to both Germany and the United States and provides seating and cooling fountains.

Queen Isabella, also known as Queen Isabella (1451–1504), is an outdoor sculpture of Isabella I of Castile, installed outside the Pan American Union Building of the Organization of American States at 17th Street and Constitution Avenue NW in Washington, D.C., in the United States.

Excluding the White House, the Lockkeeper's House, C & O Canal Extension is the oldest building on the National Mall, built in 1837 at what is now the southwest corner of 17th Street, NW and Constitution Avenue, NW, near Constitution Gardens. The building dates to a period when the south end of 17th Street, NW was a wharf and Constitution Avenue, NW was the location of a section of the Washington City Canal, which connected the Potomac and Anacostia rivers. An eastward extension of the Chesapeake and Ohio Canal (C&O Canal) met the Potomac River and the Washington City Canal at a canal lock.The 350 square foot house served the canal lock keeper, who collected tolls, recorded commerce, maintained the canal and managed traffic.

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. 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.

Ripps Island was an island located in the Potomac River in the northwest quadrant of Washington, D.C., in the United States. It was located at the mouth of Tiber Creek, in the vicinity of today's Constitution Gardens.

The Van Ness Mansion was completed for John Peter Van Ness and Marcia Van Ness in 1816 by Benjamin Henry Latrobe on 17th Street, Washington, D.C. They entertained the Madisons, James Monroe, George Washington Parke Custis and John Tayloe III at their mansion. The mansion was described as the "finest house in America". It was built on land that had been owned by Marcia's father, David Burnes, who left 500 acres along the Potomac River to Van Ness. It was one of the most expensive houses in the country, fit with hot and cold running water, a modern feature at the time, and the mansion was the first residence in the city to have that luxury. Latrobe added a feature designed to maintain a sense of privacy when food was conveyed to dining rooms. Servants accessed rotating servers from a hallway that allowed them to deliver food without entering the room. He installed them previously at the Adena Mansion in Chillicothe, Ohio. It had the country's largest and coolest wine vault. Latrop said that the Van Ness Mansion was "the best house I ever designed". It overlaid his "American rational-configuration on the kind of English residential model that impressed him during his work for and study with S. P. Cockerell."Latrobe also worked with John Peter Van Ness on the reconstruction of Washington, D.C. public buildings. Van Ness was a commissioner of the Capitol reconstruction commission, along with Richard B. Lee and Tench Ringgold. The mansion degraded over time. In 1907, the mansion was razed and the Pan American Union Building was built on the site. The stables, also designed by Latrobe, were not demolished at that time. The stuccoed building existed was located at 18th and C Streets.

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 Pan American Union Building is the headquarters for the Organization of American States. It is located at 17th Street N.W. between C Street N.W. and Constitution Avenue, Northwest, Washington, D.C.

The Memorial Continental Hall in Washington, D.C. is the national headquarters of the Daughters of the American Revolution (DAR). It is located at 1776 D Street NW, sharing a city block with the DAR's later-built Administration Building, and Constitution Hall. Completed in 1910, it is the oldest of the three buildings. It was the site of the 1922 Washington Naval Conference, a major diplomatic event in the aftermath of World War I. The building was declared a National Historic Landmark in 1972.

The Organization of American States (OAS; Spanish: Organización de los Estados Americanos, Portuguese: Organização dos Estados Americanos, French: Organisation des États américains; OEA) is an international organization that was founded on 30 April 1948 for the purposes of solidarity and co-operation among its member states within the Americas. Headquartered in the US capital, Washington, D.C., the OAS has 34 members, which are independent states in the Americas. Since the 1990s, the organization has focused on election monitoring. The head of the OAS is the Secretary General; the incumbent is Uruguayan Luis Almagro.

Columbus Memorial Library is located in the headquarters of the Organization of American States in Washington, D.C.The library offers extensive collection of books and periodicals that date back to 1535.