D.C. has a lot to offer the adventurous- free museums, festivals… and TRACK Trails! The District of Columbia (Washington, D.C.) is the capital city of the United States. Washington, D.C. is home to all three branches of the U.S. government as well as many international organizations and the embassies of 174 foreign nations. In addition to being the center of U.S. government, the District is known for its history, its many national monuments and its museums. Over the next year, there will be 13 TRACK Trails in the Greater Washington, D.C. area.