Everyone, including adults, get free admission from 5-8 p.m. every Friday and free admission all day on the last Friday of the month -- July 28, August 25, September 29, October 27, November 24, December 29.
History Colorado Museum
Kids 18 and under get free admission to the History Colorado Center in Denver every Saturday in June, July and August this summer.
History Colorado Community Museums
Kids 18 and under get free admission every day this summer until Labor Day at several History Colorado community museums including the Byers-Evans House (Denver), Fort Vasquez (Platteville), Healy House Museum & Dexter Cabin (Leadville) and others. See the list and more details here.
Four Mile Historic Park
Visit Four Mile Historic Park in Denver for free from noon to 4 p.m. on the second Friday of the month. Tour times are at 12:30 p.m., 1:30 p.m. and 2:30 p.m. Tours are first-come, first-served.
Children's Museum Tuesday
The Children's Museum of Denver offers free admission on the first Tuesday night of each month from 4 p.m. to 8 p.m. thanks to Target. Learn more on the museum's website.