The Massachusetts Bay Transportation Authority (MBTA), locally known as the "T," operates area subway, bus, and commuter rail systems. The closest subway or T stop is at Harvard Square on the Red Line, which connects the Orange, Blue, Green and Silver Lines (see map). While fares can vary according to destination, most local travel is $2.75 and requires the exact amount. Three bus routes (72 Huron Avenue, 74/75 Belmont Center, and 78 Arlmont Village) begin in Harvard Square and continue up Concord Avenue, with stops at Bond Street and Buckingham Street that are within easy walking distance to the Observatory. The bus fare is currently $2.00.