One of the nation's oldest city halls, the seat of New York City's government is also among the most impressive. Architecture aficionados flock here for the majestic rotunda, Corinthian columns and arched windows. History buffs love the Governor's Room, where everyone from Abraham Lincoln to Albert Einstein has visited. And, of course, this is also the place to see the inner workings of NYC's government—the mayor's office on one side, the City Council on the other. Reservation tours (free): individuals Thurs. 10am; groups (10–20) Mon.–Wed., 10:30am; non-reservation lunchtime tours (free): Wed., noon (register 10–11:30am at NYC tourism kiosk, southern end of City Hall Park, Broadway at Barclay St.). Tours appropriate for ages 9 and up.