Defining US: The 250th Anniversary of the United States Exhibit July 15, 2026-April 10, 2027 | DuPage County Historical Museum ( 102 E. Wesley St. ) Event Details: Hours* | Monday-Friday: 8:30A-4:30P | Saturday & Sunday: 12-4P Defining US: The 250th Anniversary of the United States explores the significant events, moments, and milestones that have shaped the United States over the course of it