The African American Civil War Memorial was dedicated #OTD# in 1998 here in #WashingtonDC#. Located at U St & Vermont Ave, the memorial honors the more than 200,000 African American soldiers & sailors who served in the U.S. Army & Navy during the Civil War.

#OTD# in 1864, Confederate forces attacked Fort Stevens in northwest #WashingtonDC#. Visiting the fort to observe the battle, President Abraham Lincoln came enemy under fire. The Confederates were defeated, ending the threat to the city. We remember Lincoln's leadership and determination at the Lincoln Memorial.

The Lock Keepers House is one of the oldest buildings on the National Mall and helps tell the story of our nation's capital. Stop by to check out the cool exhibits and learn about the history of #WashingtonDC#.

After more than 3 years of devastating combat & destruction, United Nations forces – which included the United States, South Korea, and 20 other countries – and North Korea & China signed an armistice agreement effectively ending the hostilities of the Korean War #OTD# in 1953. We remember all those who fought for freedom. #KoreanWar# #WashingtonDC#

"I love the National Mall. The stone memorials. The sunsets. The grass, trees, and water. The people. That feeling of pride and awe you experience every time you walk up the steps at the Lincoln Memorial. The words of Dr. King echo here. The legacy of millions of heroes who fought and struggled and wrote and spoke and dreamed for a more perfect union live on here. It's a privilege to work on this sacred ground. It's a treat to share stories with people from around the world. It's an honor I'll never forget." --- A #NationalMall# park ranger #WashingtonDC#

Visiting the National Mall is a walk in the park, but the distances can be deceiving. Walking from the Capitol to the Washington Monument to the Lincoln Memorial and around to the Jefferson Memorial adds up to several miles. Be sure to pace yourself in the heat, take breaks, wear sunscreen, and drink plenty of water. #WashingtonDC#

"Darkness cannot drive out darkness, only light can do that. Hate cannot drive out hate, only love can do that." This quote in the Martin Luther King, Jr. Memorial comes from "Strength to Love" - a collection of Dr. King's sermons published in the summer of 1963. #WashingtonDC#

Divisions of fresh American troops entered combat in World War I during the Second Battle of the Marne, which began #OTD# in 1918. Turning back a desperate German attack, the Allied victory on the Marne in July 1918 lead directly to the end of the war in November 1918. Honor our heroes at the World War I Memorial. #WashingtonDC#

Summer is a busy time on the National Mall and we'd have a difficult time helping all of our visitors and keeping the park looking great without our dedicated volunteers. Volunteers share their time & energy to support this special place and we can't say "Thanks!" loudly or often enough. #volunteer# #WashingtonDC#

Today is Independence Day in Argentina! To recognize the influence of George Washington and the American Revolution on the creation of a free Argentina, in 1925, the people of that country presented the United States with a statue of their own revolutionary hero, José de San Martín. It still stands along Virginia Ave. #WashingtonDC#