Fodor's Expert Review Library of Congress

Founded in 1800, the largest library in the world has more than 173 million items on approximately 838 miles of bookshelves. Only 51 million of its holdings are books—the library also has 3.6 million recordings, 14 million photographs, 5.5 million maps, 8.1 million pieces of sheet music, and 70 million manuscripts. Also here is the Congressional Research Service, which, as the name implies, works on special projects for senators and representatives.

Opened in 1897, the copper-domed Thomas Jefferson Building is the oldest of the three buildings that make up the library. The dome, topped with the gilt "Flame of Knowledge," is ornate and decorative, with busts of Dante, Goethe, and Nathaniel Hawthorne perched above its entryway. The Court of Neptune, Roland Hinton Perry's fountain at the front steps, rivals some of Rome's best fountains.

The Jefferson Building opens into the Great Hall, richly adorned with mosaics, paintings, and curving marble stairways. The octagonal Main Reading Room, its central desk surrounded by mahogany readers' tables under a 160-foot-high domed ceiling, inspires researchers and readers alike. Computer terminals have replaced card catalogs, but books are still retrieved and dispersed the same way: readers (16 years or older) open a free reader identification card issued by the library, hand request slips to librarians and wait for their materials to be delivered. Researchers aren't allowed in the stacks, and only members of Congress and other special borrowers can check books out. Items from the library's collection—which includes one of only three perfect Gutenberg Bibles in the world—are on display in the Jefferson Building's second-floor Southwest Gallery and Pavilion. Free timed-entry passes are required for entry.

 The Library puts on some amazing exhibits from its vast collection, including musical instruments, early maps, and baseball cards!