Doors Open Denver exploring 4 campuses within the city

Doors Open Denver literally opens doors to some of the city's architectural gems. It's the flagship event for the Denver Architecture Foundation.

"It really embodies the mission of the Foundation, which is it inspire people to explore our dynamic city, to experience the importance of design in our quality of life, and to envision an exceptional future for Denver," said Pauline Herrera, President & CEO of the Denver Architecture Foundation.

There are 23 tours total, 15 are in-person, guided tours, 8 are new virtual tours. There are also 16 virtual tours from previous years that you can explore.

"We're doing something a little unique this year in that we're focusing on four important campuses in our city, two of them cultural, and two of them educational. So, we are featuring the Zoo, which we've never featured before, the Denver Center for the Performing Arts complex, DU, and the Auraria Campus," Herrera told CBS News Colorado.

Among the virtual tours there are two from Colorado Springs, and one if particularly hard to get access to – the United States Air Force Academy. The Insider Tours are in-person, and lead by an expert, usually an architect, an historian, an urban planner, or someone associated with the building that has a lot of knowledge about the building.

In addition to the tours, the Denver Architecture Foundation is partnering with the Colorado Photographic Arts Center for the 5th annual, YOUR/OUR photography contest.

"It's an opportunity for photographers of all skill levels to find and photograph their favorite places and space in Denver and enter them into a contest for prizes," Herrera explained.

LINK: Tickets for Doors Open Denver

Doors Open Denver runs from September 26th to October 16th.