TOURS

Big Onion Walking Tours
212/439-1090, bigonion.com
Lively, informed historic- and ethnic-themed tours led by guides with advanced degrees in history. Check online calendar or call for meeting spots. Adults $15, seniors $12, and students $10. No reservations required; schedule subject to change in case of inclement weather.

Municipal Art Society of NY Tours
212/935-3960, mas.org/events/tours.cfm
Expert in-depth exploration of city architecture. Weekday walking tours $12; weekend walking/bus combo tour $15. Free tours of Grand Central Terminal only depart Wed. at 12:30 p.m. from the information booth in the Main Concourse.

Nosh Walks
212/222-2243, noshwalks.com
Taste your way from Odessa to Bombay. Most tours are $20 and do not include the cost of food. Sat.-Sun. only.

Radical Walking Tours
718/492-0069, radicalwalkingtours.org
See NYC through the eyes of anarchists, revolutionaries, and good old-fashioned hell-raisers. Summer schedule suspended; call for upcoming tours. $10 per tour.

Gray Line New York
800/669-0051, graylinenewyork.com
Fare is $49 for a two-day hop-on/hop-off tour by double-decker bus. Makes 42 stops in all. All tickets must be purchased online, by phone, or at the official start location, 777 8th Ave. at W. 47th St.

Pioneer Sailings From South Street Seaport Museum
212/748-8786, southstseaport.org
Schooner sailing tours of N.Y. Harbor beat the popular but noisy Circle Line any day. $30. Daily sailings May-Sept.; call for times.

NUMBERS TO KNOW