The United States’ 200th anniversary in 1976 was commonly called the Bicentennial.
The celebration marked two centuries since the Declaration of Independence was adopted in 1776. It included parades, exhibitions, concerts, historical reenactments, fireworks, and specially designed public symbols throughout the country. Philadelphia hosted a major portion of the official observance because of its connection to the Declaration and the Revolutionary era.
The Bicentennial was planned and promoted over many years, with federal agencies, state governments, cities, museums, schools, and private organizations participating. It also inspired commemorative postage stamps, coins, medals, and public works.
America250 follows the same anniversary pattern at a larger numerical milestone. “Bicentennial” means a 200-year anniversary, while “semiquincentennial” means a 250-year anniversary. A centennial is 100 years, a sesquicentennial is 150 years, and a tricentennial is 300 years.