Free tours of the inside of the historic U.S. Capitol Building begin at the Capitol Visitor Center. Advance reservations are highly recommended either though your Member of Congress or www.visitthecapitol.gov [1] (only a limited number of same-day tickets are available at the Capitol Visitor Center). The Capitol grounds are open 24 hours-a-day every day of the year, with the exception of special events. Other venues on Capitol Hill offer guide-led and self-guided tours including the Library of Congress and Supreme Court.