Summer is prime time for America’s national parks—particularly this year, which is the centennial of the National Parks Services. Publishers are working with companies that manage gift stores at the parks to reach the growing market of visitors.

The largest operator of gift shops at cultural attractions in the U.S. is Event Network. Based in San Diego, Calif., and founded in 1998, the company has stores at such historic sites such as Gettysburg National Military Park and the Alamo.

Eastern National, based in Fort Washington, Pa., was founded in 1947 to serve the national park system. It operates more than 150 stores for the National Park Service in the eastern United States, Puerto Rico, and the U.S. Virgin Islands. It is also an independent publisher, making educational products for the National Park Service. “Our publications are different from those developed by traditional publishers, because Eastern National collaborates directly with the parks to produce educational material to fit specific needs within the park,” said Erin Sweeney, inventory-replenishment manager at Eastern National.

The Western National Parks Association is the official nonprofit partner of the National Park Service and its 67 national parks in the western United States. Headquartered in Tucson, Ariz., WNPA ensures that all products, services, and programs enrich visitors’ experience.

The core purpose of these three entities is similar. Laura O’Neal, a book buyer at Event Network, summarized it by saying that her goal is “to create an extension of the guest experience at each of our partnerships.” In the case of books, O’Neal said, that means offering titles that provide educational value to park visitors by giving them more information about the different sights and exhibits that they have just seen. Books must fit with each store’s image and customer base, and Event Network tries to represent local authors and titles that focus on the region where the park is located.

Sweeney echoed O’Neal, noting that books at Eastern National’s stores are site-specific. “Few books are relevant to all our locations,” Sweeney said.

All three companies usually buy books on a nonreturnable basis, with discounts ranging from 50% to 70% off the list price. Sweeney said that most of Eastern National’s books are priced under $20 and noted that those in the $10–$15 range sell best.

Arcadia Publishing publishes books for all three companies through its Arcadia and History Press divisions. Meredith Hutchins, Arcadia’s national key-account manager, works with gift shops on a “one-on-one basis, because their needs are so individual.”

Sales to parks and historical sites are seasonal, peaking from late May to early September. In general, hardcover books sell better than paperback books, since parents seek books their children will be able to enjoy and keep as a memento of their visit to the parks. However, there are exceptions: Sweeney said that paperback books outsell hardcover in most cases at Eastern National.

Brian Jud is the executive director of the Association of Publishers for Special Sales and author of How to Make Real Money Selling Books and Beyond the Bookstore.