No matter where your interests lie—in architecture, ethnic foods, or social history—chances are good that you’ll find a tour tailor-made for you. Walking tours abound all over the city, especially in the spring and fall, with each one more imaginative than the next (“Famous Murder Sites,” “Edith Wharton’s New York”) and most priced under $15.
One of the best ways to get an overview of the city is to take a Circle Line cruise (Pier 83, West 42nd St. and the Hudson River, 212/563-3200, www.circleline.com , adults $34, seniors $29, children under 12 $21). The boats leave daily April–December. Standard daytime cruises last three hours; “express” and evening cruises last two hours.
World Yacht (Pier 81, West 41st St. and the Hudson River, 212/630-8100, $99–112 per person) offers three-hour luxury dinner cruises with live entertainment and dancing.
Gray Line Sightseeing (900 8th Ave., near 53rd St., 212/397-2600, www.graylinenewyork.com , $39–94 per person) offers over a dozen bus tours lasting anywhere from two hours to a full day. Tours are offered year-round.
For a spectacular bird’s-eye view of the city, try Liberty Helicopter Tours (212/967-4550, $125 per person, reservations required). Flights leave from the VIP heliport at 12th Avenue and West 30th Street.
What to taste the real NY? Then try one of the offerings at Scott’s Pizza Tour .
The Municipal Art Society (457 Madison Ave., near 51st St., 212/935-3960, www.mas.org ) runs an extensive series of walking tours almost daily year-round. Most of the tours focus on architecture and history.
Big Onion Walking Tours (212/439-1090, www.bigonion.com ), founded by two Columbia University  graduate students, offers some of the city’s most fun and well-researched tours. Many of the tours concentrate on New York’s immigrant history and on neighborhoods below 14th Street.
The 92nd Street Y (1395 Lexington Ave., at 92nd St., 212/415-5500, www.92ndsty.org ), a leading cultural institution, offers many excellent walking and bus tours. They’re very popular and must be reserved weeks in advance.
Harlem Heritage Tours (212/280-7888, www.harlemheritage.com ) offers about 30 different tours, ranging from “jazz nights in Harlem” to gospel walking tours.
For a hip tour of the East Village  and environs, check out Rock Junket Tours (212/696-6578, www.rockjunket.com ). “Rocker guides” lead participants past legendary rock, punk, and glam sites from the 1960s to the present.
Other unique tours focus on radical history, food, and nature. Radical Walking Tours (718/492-0069) specializes in revolutionary and labor history.
Foods of New York Walking and Tasting Tours (212/334-5070, www.foodsofny.com , $38 per person, tastings included) explores some of the most famous restaurants and food shops in Greenwich Village  and Chelsea .
Worth watching out for are the free nature walks offered in all five boroughs by the Urban Park Rangers (212/360-2774 or 866/692-4295, www.nyc.gov/parks ).
The Big Apple Greeter (212/669-8159, www.bigapplegreeter.org ) matches visitors up with enthusiastic volunteers eager to introduce the city to out-of-towners. The service is completely free and especially helpful to the disabled and tourists interested in visiting off-the-beaten-track spots.