SOUTH PARK, Colo. — The project is striking in its ambition: a sprawling research institution situated on a ranch at 10,000 feet above sea level, outfitted with 32,000 volumes, many of them about the Rocky Mountain region, plus artists’ studios, dormitories and a dining hall — a place for academics, birders, hikers and others to study and savor the West.

It is the sort of endeavor undertaken by a deep-pocketed politician or chief executive, perhaps a Bloomberg or a Buffett. But the project, called the Rocky Mountain Land Library, has instead two booksellers as its founders.

For more than 20 years, Jeff Lee, 60, and Ann Martin, 53, have worked at a Denver bookshop, the Tattered Cover, squirreling away their paychecks in the pursuit of a single dream: a rural, live-in library where visitors will be able to connect with two increasingly endangered elements — the printed word and untamed nature.

“It’s everything, really,” Ms. Martin said of the role the project has played in her life, and that of her husband, Mr. Lee. “It’s not really about us. It’s something for Colorado, for this region.”