Call it a New Year's gift.

Beginning next week, a potential treasure trove of eclectic, valuable modern literature will be loaded onto trucks and driven to Philadelphia and the University of Pennsylvania's Rare Book and Manuscript Library.

An anonymous donor has purchased the 200,000-plus item inventory of the Gotham Book Mart - a Midtown Manhattan literary landmark that closed in 2007 - and donated it to Penn Libraries.

Once the materials arrive from the Connecticut warehouse where they have been stored since Gotham closed, it will take Penn experts approximately two years to sort, catalogue and prepare the collection for public consumption.

"It's our New Year's baby," said David McKnight, director of Penn's Rare Book and Manuscript Library, who is overseeing the Gotham project.

Among the works are materials from the personal libraries of Anais Nin and Truman Capote, and books printed by the Black Sparrow Press, a noted publisher of avant-garde literature. And though Penn libraries have not previously specialized in this type of modern works, "it's an important area of study and teaching for Penn faculty and graduate students," Traister said.

In time, the material will be available to students, researchers, scholars and members of the public. Information about the collection will also be listed online and some materials will be made available digitally through a Gotham Book Mart Web site.

"It's going to be accessible to Philadelphians," McKnight said. "Our doors are open."

The Gotham Book Mart opened in 1920, and quickly became not just a place to buy modern literature and rare books but also a literary salon, where such luminaries as Nin, Dylan Thomas, and Salvador Dali once gathered. Allen Ginsberg and Amiri Baraka worked there as clerks in their youth.

In 2004, a benefactor kept the shop from closing, but the changing habits of the book-buying public and the dire financial straits of Gotham's last owner doomed the business. Gotham finally shut its doors in the spring of 2007.

The collection is valued at "several million dollars," experts believe. The donor who purchased the collection is known to Penn officials but wishes to remain anonymous.

Some of Gotham's most valuable first editions have been sold at auction, but given the size of the collection, experts predict that many valuable works remain. Daniel Traister, curator of research services at the rare books library said that no one knows exactly what they will find when the trucks arrive in Philadelphia.

"The collection is so big that no single person from the university has really seen it," Traister said. "What we've seen are descriptions."

And while Penn's rare book library has a heavy concentration in pre-1850 materials, the Gotham collection provides a new dimension.

"It should be material that sheds light on a lot of different aspects of the modernist movement," said Traister. "As a gift, it simply has the power to be transformative for the kind of study and research that we can support."

Given the recent closing of Robin's Bookstore in Center City, which was believed to be the oldest book shop in Philadelphia, the Gotham collection takes on special significance, McKnight said.

"It was such a valued place in the literary community, and as a rare-book librarian, I'm always concerned about seeing shops like this close," McKnight said of Robin's Bookstore. "I've watched a few bookstores die in my time, and it's always sad."