Colorado Celebrates 150 Years
Sesquisemiquincentennial
In 2026, the United States will mark the 250th anniversary of the Declaration of Independence—our nation’s semiquincentennial. At the same time, Colorado will mark the 150th anniversary of our entrance into the Union—our state’s sesquicentennial. As the Centennial State, Colorado is the only one who will observe twin anniversaries—our Sesquisemiquincentennial.