During much of the 19th and 20th centuries, the Washington Navy Yard was the most recognizable symbol of the United States Navy in the nation's capital. The shipyard built a number of the Navy's first warships and repaired, refitted, and provisioned most of the frigates, sloops, and other combatants of the fledgling naval service. The masts and rigging of USS Constitution were a common site on the banks of the Anacostia River. Booming cannon became a routine sound in southeast Washington during the mid-19th century as Commander John A. Dahlgren, “father of American naval ordnance,” test-fired new guns for the fleet. The Naval Gun Factory's fire and smoke-belching blast furnaces, foundries, and mills gave birth to many of the fleet's weapons, from small boat howitzers to the enormous 14-inch and 16-inch rifles that armed the naval railway batteries in World War I and the Iowa-class battleships in World War II and the Cold War. Rear Admiral David W. Taylor inaugurated a new era in ship development when he used scientific measurements in his Experimental Model Basin to test the properties of prototype hulls. Before and after World War I, the pioneers of naval aviation experimented in the Anacostia and navy yard facilities with various seaplane types, shipboard catapults, and other equipment that would soon revolutionize warfare at sea. The Washington Navy Yard has been a witness to history—to the evolution of the United States of America from a small republic, whose ships were preyed upon by Barbary corsairs and whose capital was burned by an invading British army, into a nation of enormous political, economic, and military power and global influence. The Civil War that so dramatically altered American society swirled around and through the Washington Navy Yard. American presidents, first ladies, foreign kings and queens, ambassadors from abroad, legendary naval leaders, national heroes and villains, and millions of citizens have all passed through Latrobe Gate during the yard's 200-year existence. The Washington Navy Yard has also been the workplace for tens of thousands of Americans, a familiar landmark in the District of Columbia, and a valued member of the Washington community. Throughout the 19th and 20th centuries, ship riggers, hull caulkers, iron and bronze smiths, joiners, millwrights, machinists, foundrymen, boilermakers, and tool and die makers; skilled workmen and laborers; naval officers, bluejackets, and marines have earned their livings within the walls of the navy yard. Numerous Americans, white and black, male and female, have spent their entire working lives at the yard building warships, manufacturing guns, testing vessel and aircraft models, training sailors, or administering the needs of American combatants steaming in the distant waters of the world. Navy yard workers, as many as 26,000 men and women at one point in 1944, contributed to the success of U.S. arms in the Spanish-American War, World Wars I and II, the Cold War, and Operation Desert Storm. Yard workers, most of them residents of the District, Maryland, and Virginia, over the years have helped local authorities extinguish fires, hold back flood waters, rescue victims of natural disasters, and care for needy members of the surrounding neighborhoods. They have helped federal authorities put together national celebrations to mark the end of the country's wars, repair the Capitol and other government buildings, receive the sacred remains of unknown U.S. servicemen from overseas, stage presidential inaugurations, and welcome foreign dignitaries to American soil. Above all, they have loyally served the United States and the U.S. Navy. This richly illustrated history was written in the bicentennial year to highlight the importance of the Washington Navy Yard and its employees to the nation, the Navy, and the District of Columbia. It touches on the major activities of the facility and on some of the yard's past workers and significant visitors.