These organizations provide free/discounted admission on select days of the year. Free Days 2019 is funded, in part, by the residents of Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas and Jefferson counties via the SCFD 0.1% sales and use tax.

Here is the calendar and bookmark download: http://scfd.org/p/free-days-calendar.html

Here are just a FEW of the places offering free days:

Denver Zoo

Clyfford Still Museum

Denver Art Museum

Children's Museum of Denver

Museo de las Americas

Denver Museum of Nature & Science

Plains Conservation Center

Four Mile Historic Park

Denver Botanic Gardens

Denver Firefighters Museum