If you like geometry, you’ll love Chicago. The grid is straight out of math class, except Lake Michigan ate the right half of your homework. Everything starts at State and Madison, whose coordinates on the numeric plan that describes the whole city are 0 and 0. Addresses move out from there, with each 800 representing about a mile: 800 N. State is about a mile north, 800 W. Madison a mile west, 800 S. State a mile south, and 800 E. Madison underwater. Each street has its own number: Halsted, for instance, runs north-south at 800 West from top to bottom. And the streets at multiples of 400 tend to be major thoroughfares. If you live near Irving Park Road you tell people you live just south of “forty-hundred north.” Armed with a street guide and an address, you’ll always know exactly where you need to be. Just to keep it from being too easy, there are a few diagonal streets, some of which follow the paths of long-gone wagon trails; an address will give you one coordinate, but you’ll have to ask for a cross street for the other. Out here on the prairie, the grid substitutes for landscape: the numbers tell which way you’re headed and how far you have to go.

Neighborhoods are odd-sized rooms laid over this rigid foundation. In the 1920s sociologists semiofficially divided the city into “community areas,” now 77 in number. Your actual neighborhood may vary: Edgewater is a community area and a recognized neighborhood: it also contains Andersonville, which you might well also call a neighborhood. Neighborhoods are different from wards, of which there are 50, each represented by an alderman in the City Council. At a Center for Neighborhood Technology Web site (newschicago.org) you can type in an address and learn lots of cool things about the property and the community area it’s in.

Expressways respect neither grid nor neighborhood, and knowing their names is like a secret Chicago handshake. From southeast to northwest through the city the name of Interstate 90 changes four times: Skyway, Dan Ryan, John F. Kennedy, Northwest Tollway. Interstate 94 is worse, entering Illinois as the Kingery, turning north to become the Bishop Ford, feeding into the Ryan and the Kennedy, and then veering off north as the Edens. (Got that? If not, tune out the radio traffic reports and bookmark gcmtravel. com/gcm/maps_chicago.jsp.) The interstate highway system insists that the Ryan and Kennedy are east-west roads, even though in Chicago they run mostly north-south. To get to Milwaukee, you’ll head “west” on I-94.

There are two local car-sharing services: the four-year-old locally grown nonprofit I-GO (founded by the Center for Neighborhood Technology and a member of the Flexcar network) and the older, larger, brand-new-to-Chicago Zipcar. I-GO has locations in more Chicago neighborhoods. Both services have affiliates in other cities–you may prefer I-GO if you spend a lot of time in Atlanta, Zip if you favor Chapel Hill or Minneapolis–and complicated pricing schemes that are somewhat difficult to compare. But unless you drive all the time, either is cheaper than owning.

Parking downtown is extremely expensive, and traffic everywhere can be exasperating. Chicago on foot is the real deal, with people, textures, and buildings. But not everyone has the stamina to walk everywhere, nor do we all have the equipment and courage for bicycling, or the cash for cabs. That’s where the Chicago Transit Authority’s elevated trains, subways, and buses come in. It’s not illegal to use money on them, but it’s getting close. Buses still take exact change, but you pay extra–$2 instead of $1.75 with a card–and you can’t buy any transfers. Trains require that you buy a card in advance, either a transit card, available for cash from machines at stations, or the newer Chicago Card or Chicago Card Plus (chicago-card.com).

The rectangle of elevated tracks running around the heart of downtown above Lake, Wabash, Van Buren, and Wells gave the Chicago Loop its name. An engineering gimmick, it allows the trains on the Brown, Purple, Orange, and

Pink lines to come into town and then turn around without reversing direction. This neat idea is the product of stubbornness and betrayal, not good government. In the 1890s, entrepreneur/

crook Charles Tyson Yerkes tried to minimize opposition by building it one leg

at a time. He had to shell out as much as $100 per foot of frontage to gain the consent of adjacent property owners for the first three legs. But the owners along Van Buren Street, the final link, couldn’t be bought. So he set up another company that applied for a franchise to build that leg plus an extension running a mile west across the Chicago River to Halsted. The City Council granted the franchise, the western property owners outvoted the downtowners, and Yerkes completed the Loop. Then he screwed his supporters by not building the western extension–and soon left town for London.

The CTA will get you to the near-in suburbs of Rosemont, Oak Park, Forest Park, Cicero, Evanston, Skokie, and Wilmette. Beyond that, you’ll have to deal with Pace (suburban buses) or Metra (suburban rail, which goes to Wisconsin and Indiana if you’re patient). Technically CTA, Pace, and Metra are all ruled by the Regional Transportation Authority. But in 32 years RTA has yet to unify its three fiefdoms’ ticket schemes. Check the latest at rtachicago.com/travel/

fareinfo.asp and plan trips at tripsweb.rtachicago.com.

Chicago hasn’t done a lot to enable more people to dispense with their cars, especially those who can’t afford them in the first place. Instead the CTA seems to specialize in making relatively small plans, like expanding the capacity of the fast-growing northwest-side Brown Line. The mayor wants to add a downtown terminal to serve Midway and O’Hare airports, which are already quite well served. In May the CTA held public meetings to discuss a circle line that would swing around the city center about two miles out. Meanwhile, miles of Chicago lie south of 95th Street, the last stop on the Red Line, including largely black neighborhoods like Roseland and Altgeld Gardens that arguably need good public transportation more than others need theirs enhanced.

The CTA is more than a way to get around, it’s a way of life (ctatattler.com and community.live journal.com/chicago_el). Like any way of life, it’s simultaneously the object of love and loathing.

It doesn’t matter how often I’ve waited half an hour for a bus and then watched two or three arrive in a row–I still care. Every year, when the agency repeats the traditional stations of the cross (financial crisis, threatened cutbacks, scourging by legislators, last-minute reprieve), I fret as if it were the first time. “The food is terrible,” said the restaurant critic, “and there’s not enough of it.”

Art accompanying story in printed newspaper (not available in this archive): photo/Joeff Davis.