Introduction to the Museum of American History: The National Museum of American History is the largest history museum in the United States and a subsidiary museum of the Smithsonian Institution. Located on Constitution Avenue in Washington. It was built on the basis of exhibits from the 1876 United States Centennial Exposition and opened in 1964. It was then called the National Museum of American History and Technology. The museum is a five-story white marble building with a length of 175 meters, a depth of 91.5 meters, and a height of 36.7 meters. It is the largest national comprehensive history museum in the United States. It collects more than 17 million historical relics related to American industry, agriculture, science, technology, politics, military, finance, handicrafts, transportation, post and telecommunications, textiles, medicine, clothing, music, folk customs and other aspects. It truly reflects the society, culture, scientific and technological traditions of the United States and the evolution of the American body, allowing people to better understand the United States and the people of different races living here.