The building is a five-story white marble building with a length of175m, a depth of 91.5m and a height of 36.7m. It is the largest national comprehensive history museum in the United States. There are more than 0/70,000 pieces of historical relics/kloc-related to American industry, agriculture, science, technology, politics, military affairs, finance, handicrafts, transportation, posts and telecommunications, textiles, medicine, clothing, music and folk customs. It truly reflects the evolution of American society, culture, scientific and technological traditions and American national system, so that people can better understand the United States and people of different races living here.