The Ontario Museum of History and Art aims to expand the community's knowledge of local culture through educational programs, exhibits and special events. The museum exhibits in detail, the life and people of the Inland Empire and the docents organize various outreach programs and field trips throughout the year. One of the highlights during Autumn is the Dia de los Muertos festival, when local artists showcase the macabre through painting, sculpture and crafts. Every year the event draws in thousands over the Halloween season.

If you ever wanted to learn about the history of Ontario, Upland, Montclair or the bizarrely named Rancho Cucamonga, then you have come to the right place. When it was established in 1965, the museum was named the Chaffee Communities Cultural Center after its affiliation with Inland Empire businessmen, William and George Chaffee. In 1997, the name changed to honor local benefactor Ada Cooper, a woman who made a philanthropic donation to the center. Inside, visitors will find exhibits, objects and documents that highlight the development and lives of people in this Southern California region. Moreover, the museum also houses an auditorium for performances, talks, workshops and concerts.

The African American Museum of Beginnings has art, artifacts and cultural events that feature and highlight the African arts, culture and civilization from the bygone era. The Pomona gallery displays art and sculpture from various African cultures as well as those from the United States and beyond. Their assemblage features creative exhibits made by the town's preschoolers, apart from some breathtaking art works depicting the heritage, milestones and contemporary issues of the African community spread in different parts of the world.

This museum is not named after that lovable alien character from the 80's sitcom, but after high school teacher and amateur paleontologist Raymond Alf. He began as a hobbyist in 1936 and with trip-after-trip into the Mojave Desert, Alf garnered a vast collection of fossils. The museum is located on the campus of The Webb Schools, a private high school founded by Thompson Webb and it is the only museum in the U.S. with its location at a prep school. There are two main exhibits, the Hall of Footprints which features some of the most varied fossil 'trackways' in the world and the Hall of Life that expounds upon the Earth's 4.5-billion year history.