Built between 1803 and 1812 in Federal style, and the oldest such structure in the U.S. that remains home to its original purpose, City Hall features a number of pleasing architectural details, including a dome and cupola. The interior houses the mayor's office and the city council, as well as a permanent art and history collection. At the northern end of City Hall Park, you'll find the stunning Tweed Courthouse, built in 1870 by the notorious "Boss" Tweed—construction costs were originally budgeted at US$250,000 but ballooned to more than US$14 million. You'll find the entrance to the pedestrian ramp of the Brooklyn Bridge there, too. Individual tours of City Hall and Tweed Courthouse are offered Thursday at 10 am and Friday at 2 pm; tours of City Hall alone are offered Monday and Wednesday-Friday at 10 am. Group tours are available. Tours are free; reservations are necessary and may be made at http://www.nyc.gov/html/artcom/html/tours/reserve_tour.shtml. A first-come, first-served tour, limited to 20 people, is offered Wednesday at noon. 250 Broadway at Chambers Street (subway line J, M or Z to Chambers Street; 4, 5 or 6 to Brooklyn Bridge-City Hall; R to City Hall), Manhattan, New York City. Phone 212-639-9675. http://www.nyc.gov.