AUGUSTA — The Maine State Museum will open its doors free of charge to all Museum Day ticketholders on Saturday, Sept. 21, as part of Smithsonian magazine’s 15th annual Museum Day, a national celebration of culture and learning.

For free admission, visit Smithsonian.com/museumday. On that day, the museum will be open from 10 a.m. to 4 p.m., according to a news release from the Augusta museum.

“Our visitors often think of the Maine State Museum as a kind of mini-Smithsonian,” said Museum Director Bernard Fishman, according to the release. “This is a compliment to both institutions and makes our participation in Museum Day a good fit for the Maine State Museum. Both museums use objects from nature and culture to enhance understanding and knowledge, and convey the incredible richness and diversity of the many kinds of worlds that surround us.”

Smithsonian magazine recognizes the extraordinary power of museums, and other cultural institutions, to provide visitors with insight and inspiration. Museum Day represents a nationwide commitment to boundless curiosity and the pursuit of knowledge. More than 250,000 people downloaded tickets for last year’s event. More than 1,500 museums nationwide are expected to participate in Museum Day this year.

Visitors who present the Museum Day ticket will gain free entrance for two at participating museums and cultural institutions for one day only. One ticket is permitted per household, per email address.

For more information about Museum Day and a list of participating museums and cultural institutions, visit Smithsonian.com/museumday.

For additional information about the Maine State Museum’s exhibits and programs, visit mainestatemuseum.org.