Denver, Colorado, offers a variety of free activities and attractions that cater to different interests.
Here are some great options:

Denver Fast Facts
Nickname: Mile high city
Time Zone: Mountain
Airport: https://www.flydenver.com/
Served by: Delta, Frontier, Jet Blue, Allegiant, Alaska Air, Southwest and several international airports
Altitude: 5,280 elevation
Interstate: I-70Known for: street art, riverside parks and outdoor opportunities.

Denver Visitor Center
1555 California St Ste 300
Denver, CO 80202
Phone: (303) 892-1112

Hammond’s Chocolate Factory Tour
5735 Washington St.
Denver, CO 80216
Phone: (303) 333-5588
https://hammondscandies.com/

Colorado State Capitol
200 E. Colfax Ave.
Denver, CO 80203
Phone: (303) 866-2604
Stained glass, murals, rotundaFree Tours Monday through Friday
https://www.denver.org/listing/colorado-state-capitol/3679/

US Mint – Free
Age 7 and older.
Tickets available from Tour Information Window on Cherokee Street between Colfax Avenue and West 14th Avenue.
Same-day tours only; no advance tickets are available. Tickets will are  available on a first-come, first-served basis and are limited to 5 per person. https://www.usmint.gov/about/mint-tours-facilities/denver/visiting-the-denver-mint

16th Street Mall
900 16th St, Denver, CO 80202
Phone: (720) 974-1777
A mile-long pedestrian promenade with shops, restaurants, and street performers.
https://www.the16thstreetmall.com/

Union Station -Depot Circa 1881
1701 California St.
Denver, CO 80202
Tallest building in the west at the time of construction. Restored beaux-arts landmark in Lower Downtown Denver with lots of shops and restaurants. Spend an afternoon or an afternoon. Wear walking shoes though. The station still serves as a multi-modal transit hub for Amtrak rail and RTS bus and rail services. https://www.denverunionstation.com/