With its famous ski slopes, world-class resorts, and must-visit restaurants and attractions, Colorado has earned a reputation for being a fun, albeit expensive place to live or visit. Fortunately, there are still a few places that are affordable and some that are even free, including these 7 little-known Colorado museums:

1. Peterson Air & Space Museum (Colorado Springs)

Located on the Peterson Air Force Base is the exciting Peterson Air & Space Museum; one of only 12 United States Air Force Field museums that features everything from historical replicas to special events, and authentic hangars and planes. Whether you take a guided tour or walk around at your leisure, you will find something to love at Peterson!

Address: 150 Ent Avenue, Peterson AFB, CO 80914

2. Moraine Park Museum and Amphitheater (Estes Park)

Tucked away inside of Rocky Mountain National Park, Moraine Park is a gorgeous outdoor oasis that houses not only a beautiful amphitheater but must-see museum as well. What is there to do inside? We recommend learning more about the area and shopping around the unique gift shop.

Address: 3 Bear Lake Road, Estes Park, CO 80517

3. Limon Heritage Museum (Limon)

Open from Memorial Day through Labor Day (with private, off-season tours available upon request), the Limon Heritage Museum is an impressive Complex comprised of an old Rock Island Depot, a one-room schoolhouse, trains, and stunning Exhibit Building. In addition to the museum itself, the Limon Heritage Museum hosts its annual Heritage Festival, a meet-and-greet with Santa, and more.

Address: 701 1st Street, Limon, CO 80828

4. Arvada Center for the Arts (Arvada)

While the Denver area may generally be considered to be expensive, there are a handful of fun and free things to do, including a tour of the Arvada Center for the Arts' Arvada Historical Museum! Opened in 1976, the Arvada Historical Museum has everything from mining-era replicas to the old Haines log house and hands-on agricultural equipment.

Address: 6901 Wadsworth Boulevard Arvada, CO 80003

5. Red Rocks Amphitheatre & Visitor Center (Morrison)

What? You didn't think that Moraine Park was the only free amphitheater museum in Colorado, did you? One of the best concert venues in the country also features one of the best music museums in Colorado, a la the fascinating Colorado Music Hall of Fame and its colorful exhibits, videos, and various memorabilia.

Address: 18300 West Alameda Parkway, Morrison, CO 80465

6. Colorado School of Mines Geology Museum (Golden)

Are you of the viewpoint that geology rocks? (See what we did there?) Then get ready to be amazed at the Colorado School of Mines Geology Museum and its 15,000-square-feet of fossils, minerals, and - of course - rocks.

Address: 1310 Maple Street, Golden, CO 80401

7. Frisco Historic Park and Museum (Frisco)

The next time you visit the mountains, don't pass up your chance to visit the exciting Frisco Historic Park, which demonstrates the area's rich history via its original homes and buildings.

Address: 120 Main Street, Frisco, CO 80443

How many of these free museums have you visited? Which is your favorite? Let us know your thoughts in the comments! For even more inexpensive things to do around the Centennial State, check out This 100-Year-Old Candy Factory In Colorado Gives Free Tours That Your Whole Family Will Love.