15th Street and Constitution Avenue, NW 202-426-6841 or 1-800-967-2283 Open daily 9 am - 4:45 pm, except Christmas and Independence Day. Admission is free, although tickets are required. Same-day timed tickets may be obtained at the ticket kiosk on 15th Street at the base of the monument, or advanced tickets may be obtained for a small fee from Ticketmaster at www.ticketmaster.com
. The famous marble obelisk, honoring America's first president, is the tallest structure in the nation's Capitol and will remain so by law. Elevators will take you to the top of the 555-foot monument for a spectacular view of the city.