National Arboretum, Structure
National Arboretum Historic District: The National Arboretum celebrates the diverse plant life of the United States with a 446-acre center for nature research and preservation in the nation’s capital.
Although Congress passed a law authorizing the Secretary of Agriculture to establish a national arboretum in DC in 1927, more than three decades passed before the U.S. National Arboretum was open to…