The Washington Metropolitan Area Transit Authority (WMATA) operates the Washington Metro, the city's rapid transit system, as well as Metrobus. Both systems serve the District and its suburbs. Metro opened on March 27, 1976 and presently consists of 86 stations and of track. With an average of about one million trips each weekday, Metro is the second-busiest rapid transit system in the country, after the New York City Subway. Metrobus serves over 400,000 riders each weekday, making it the nation's sixth-largest bus system. The city also operates its own DC Circulator bus system, which connects commercial areas within central Washington.