The Washington Monument is an obelisk that is located at the western end of the National Mall.  It is a memorial to first U.S. President George Washington.

Construction was started in 1848 and was completed in 1884.  It stands at over 555 feet tall and is visited by more than 800,000 visitors per year.

The Tomb of the Unknowns is a monument in Arlington National Cemetary that is dedicated to American soldiers who have died but not been identified.  The Tomb has an inscription that says: “HERE RESTS IN HONORED GLORY AN AMERICAN SOLDIER KNOWN BUT TO GOD”.

The Lincoln Memorial, on the extended axis of the National Mall in Washington, D.C., is a United States Presidential Memorial built to honor 16th President Abraham Lincoln. The architect was Henry Bacon, the sculptor was Daniel Chester French, and the painter of the interior murals was Jules Guerin.

The building is in the form of a Greek Doric temple and contains a large seated sculpture of Abraham Lincoln and inscriptions of two well-known speeches by Lincoln. The memorial has been the site of many famous speeches, including Martin Luther King’s “I Have a Dream” speech, delivered on August 28, 1963, during the rally at the end of the March on Washington for Jobs and Freedom.

The Arch, designed by Finnish-American architect Eero Saarinen and structural engineer Hannskarl Bandel, stands 630 feet (192 m) tall, and is 630 feet (192 m) at its widest point. It is the tallest habitable structure in St. Louis (taller than One Metropolitan Square, the tallest building), and the second tallest in Missouri (behind One Kansas City Place in Kansas City).  It is part of Jefferson National Expansion Memorial.

The cross-sections of its legs are equilateral triangles, narrowing from 54 feet (16.5 m) at the base to 17 feet (5.2 m) at the top. Each wall consists of a stainless steel skin covering reinforced concrete from ground level to 300 feet (91 m) or carbon steel and rebar from 300 feet (91 m) to the peak. The interior of the Arch is hollow and contains a unique transport system leading to an observation deck at the top. The interior of the Arch also contains two emergency stairwells of 1076 steps each, in the event of a need to evacuate the Arch or if a problem develops with the tram system.

Located on a 12 acre island, the Statue of Liberty Enlightening the World was a gift of friendship from the people of France to the people of the United States and is a universal symbol of freedom and democracy. The Statue of Liberty was dedicated on October 28, 1886, designated as a National Monument in 1924 and restored for her centennial on July 4, 1986.