Chicago's Loop is spanned by the Chicago Pedway, six miles of indoor pedestrian walkways. The Chicago Pedway connects the Red Line, the Blue Line, and the Metra; it links the James R. Thompson (State of Illinois) Center, the Daley Center, and City Hall; it's even home to an express DMV, where it took me only five minutes to renew my driver's license! Not much information about the Pedway is available online. The map available on the City of Chicago's website (.pdf) is over two years out of date. The map available on chicagopedwaytour.com is more recent, but incomplete. (Don't miss the cool cross section of the Pedway at the bottom of that page.)
The most recent Chicago Pedway data can be found on the City of Chicago's GIS Data page. I made several maps of the Pedway with this data. Download the KML for the map at the top of this page. The Pedway is divided into segments: the first map has segments labeled with their official ID number, which you can cross-reference against the Pedway data table at bottom to find the name and length in feet of any segment. I assigned segments colors to distinguish them from nearby segments. Some segments are unlabeled since their label would overlap the label of a nearby segment: 9 is the blue segment immediately south of 8 (yellow); 14 is the blue cross immediately east of 11 (red); 21 is the blue ring inside 20 (yellow); 23 is the blue segment immediately north of 24 (yellow); and 28 is the yellow segment immediately south of 27 (red). I've also provided closeup maps of four areas of the Pedway to clarify which segments are which, as well as an unlabeled map to give a clearer idea of where the Pedway runs. I hope these maps are helpful to Pedway explorers.
| 1 | 203 - RENAISSANCE HOTEL CONCOURSE | 1956 |
| 2 | AON CENTRE - FAIRMONT HOTEL WALKWAY | 184 |
| 3 | AON CENTRE - LAKESHORE ATHLETIC CLUB CONCOURSE | 538 |
| 4 | AON CENTRE LOBBIES | 433 |
| 5 | APPAREL CENTER GROUND LEVEL WALKWAY | 733 |
| 6 | APPAREL CENTER UPPER LEVEL WALKWAY | 271 |
| 7 | BC / BS - MONROE GARAGE & GRANT PARK CONCOURSE | 1182 |
| 8 | CHASE TOWER GROUND LEVEL CONCOURSE | 280 |
| 9 | CHASE TOWER LOWER LEVEL CONCOURSE | 935 |
| 10 | CHICAGO TITLE & TRUST CENTER WALKWAY | 270 |
| 11 | CITY HALL - 120 NORTH LASALLE WALKWAY | 283 |
| 12 | CITY HALL & COUNTY - CULTURAL CENTER CONCOURSE | 2836 |
| 13 | CITY HALL & COUNTY - THOMPSON CENTER WALKWAY | 247 |
| 14 | CITY HALL & COUNTY BUILDING HALLWAYS | 682 |
| 15 | DALEY PLAZA - BRUNSWICK BUILDING CONCOURSE | 813 |
| 16 | FAIRMONT HOTEL - PARK MILLENNIUM CONCOURSE | 833 |
| 17 | GARLAND COURT - R.R.DONNELLEY WALKWAY | 280 |
| 18 | GRANT PARK SOUTH PARKING WALKWAY | 921 |
| 19 | JACKSON CTA SUBWAY STATION CONNECTOR | 852 |
| 20 | JAMES R. THOMPSON CENTER GROUND LEVEL CONCOURSE | 928 |
| 21 | JAMES R. THOMPSON CENTER LOWER LEVEL CONCOURSE | 779 |
| 22 | MACY'S - 25 E WASHINGTON CONCOURSE | 630 |
| 23 | MERCHANDISE MART GROUND LEVEL CONCOURSE | 2079 |
| 24 | MERCHANDISE MART UPPER LEVEL CONCOURSE | 1119 |
| 25 | METRA MILLENNIUM PARK STATION CONCOURSE | 1660 |
| 26 | METRA VAN BUREN STATION WALKWAY | 748 |
| 27 | MICHIGAN PLAZA - ILLINOIS CENTER CONCOURSE | 920 |
| 28 | MICHIGAN PLAZA WALKWAY | 691 |
| 29 | MILLENNIUM & N GRANT PARK GARAGE WALKWAY | 1814 |
| 30 | N LEO BURNETT - S LEO BURNETT WALKWAY | 385 |
| 31 | OGILVIE GROUND LEVEL CONCOURSE | 845 |
| 32 | OGILVIE METRA STATION | 1723 |
| 33 | OGILVIE UPPER LEVEL - 2 RIVERSIDE CONCOURSE | 927 |
| 34 | ONE ILLINOIS CENTER - COLUMBUS PLAZA CONCOURSE | 855 |
| 35 | ONE ILLINOIS CENTER - TWO ILLINOIS CENTER WALKWAY | 202 |
| 36 | PRUDENTIAL PLAZA - AON CENTRE CONCOURSE | 665 |
| 37 | RENAISSANCE HOTEL WALKWAY | 276 |
| 38 | SMURFIT STONE WALKWAY | 90 |
| 39 | THOMPSON CENTER - CONCOURSE AT 203 WALKWAY | 203 |
| 40 | THREE BANK ONE PLAZA - 33 N DEARBORN CONCOURSE | 879 |
| 41 | THREE ILLINOIS CENTER - SWISS HOTEL CONCOURSE | 755 |
| 42 | TWO ILLINOIS - THREE ILLINOIS CONCOURSE | 990 |
| 43 | TWO ILLINOIS CENTER - HYATT REGENCY WALKWAY | 201 |
| 44 | TWO PRUDENTIAL PLAZA CONCOURSES | 278 |