Walking Tour 1: The Loop

Start: The Willis (Sears) Tower.

Finish: Harold Washington Library Center.

Time: 1 1/2 hours.

Best Time: Daytime, particularly weekdays when downtown businesses are open.

Worst Time: Late evening, after shops and offices have closed.

Walk through the Loop's densely packed canyon of buildings, and you'll feel the buzzing pulse of downtown. While you'll pass plenty of modern high-rises, you'll also get a mini-lesson in architectural history as you survey the progression of the city's skyscrapers.

Start the tour at:

1. The Willis (Sears) Tower

Okay, so this 110-story megatower is no longer the world's tallest building. It's not even the Sears Tower anymore, since the naming rights were bought by the London-based insurance broker Willis Group in early 2009. But "Willis Tower" (gulp) is still referred to as the Sears Tower by defiant Chicagoans and remains a bold symbol of the city. If it's a clear day (and you've got the time), take a trip up to the Skydeck before heading off on your tour: To the east you'll look out over the lake, to the northwest you can watch planes take off from O'Hare Airport, and to the north you'll be able to see all the way to Wisconsin.

Walk north along Wacker Drive until you arrive at:

2. 333 W. Wacker Dr.

Proof that Chicago inspires architectural creativity, this 1983 office building was designed to fit a rather awkward triangular plot (previously thought suitable only for a parking lot). But architectural firm Kohn Pedersen Fox came up with a brilliant solution, designing a curved facade that echoes the bend of the Chicago River. Walk out to the Franklin Street Bridge to get the full effect of the building's mirrored surface, which reflects the surrounding cityscape in ever-changing shades of blue, green, and gray.

Across the river you'll see:

3. The Merchandise Mart

Touted as the world's largest commercial building, the Mart is a Chicago landmark as much for its place in the history of American merchandising as for its hulking institutional look. Completed in 1931, it's occupied mostly by furniture and interior-design businesses. Perched on top of the pillars that run the length of the building are oversized busts of American retail icons, including Julius Rosenwalk (Sears), Frank W. Woolworth, and Aaron Montgomery Ward.

Walk 2 blocks east along Wacker Drive. At LaSalle Street, turn right and continue 2 blocks to Randolph Street. Turn left (east), go half a block, and you'll be standing in front of:

4. The James R. Thompson Center

This postmodern cascade of glass and steel is -- depending on your point of view -- the pinnacle or the low point of architect Helmut Jahn's career. Home to offices of the Illinois state bureaucracy, it was designed to promote the idea of open government: The transparent glass walls inside allow citizens to see their tax dollars at work. Step into the atrium to check out the beehivelike atmosphere; you can even ride a glass elevator up to the 17th floor if you're not afraid of heights.

Cross Randolph Street and head south along Clark Street. On the left you'll come to an open space known as:

5. Daley Plaza

Shadowed by the looming tower of the Richard J. Daley Center -- a blocky dark monolith of government offices -- this square was named for the legendary mayor and longtime czar of Cook County politics. While you're here, go ahead and do what tourists do: Take a picture in front of the Picasso sculpture.

Walk back up to Randolph Street and head east. At the corner of Randolph and State sts., you'll see two local landmarks: the marquee of the Chicago Theatre to your north and the block-long Macy's (previously Marshall Field's) to the south. Continue south along State Street until you reach:

6. The Reliance Building

Now a Staypineapple hotel, this building may not look impressive, but it's famous in the world of architecture. Completed in 1895, it had a remarkably lighter look than its bulky predecessors, thanks to steel framing that allowed for the extensive use of glass on the facade. It also marked the first use of the "Chicago window": a large central pane of glass flanked by two smaller, double-hung windows used for ventilation. To get a glimpse of what it looked like when it was an office building, take one of the hotel elevators up to one of the guest room floors, which still have the original tile flooring and glass-windowed office doors.

Continue south along State Street until you reach Adams Street. Ready to pause for a bite or a drink? Then turn right (west), go half a block, and stop at:

7. Take a Break 

In a world of chain coffee shops and fast-food joints, the Berghoff, 17 W. Adams St. (tel. 312/427-3170), feels like a flashback to Old Chicago. The bar of this 100-year-old restaurant serves several different house brews on tap, along with sandwiches and appetizers. (For a nonalcoholic treat, try the homemade root beer.) If it's lunchtime, grab a table in the main dining room; although the menu has been modified for modern, lighter tastes, the Wiener schnitzel and spaetzle are house classics.

Go 2 blocks west along Adams Street until you reach LaSalle Street. Turn left (south) and you'll be at:

8. The Rookery

Built between 1885 and 1888, the Rookery represents a dramatic transition in Chicago architecture. (It's also one of the only surviving buildings designed by noted architect Daniel Burnham, along with the Reliance Building, above.) The name refers to the previous building that sat on this site, Chicago's original City Hall, which was a favorite spot for nesting birds; today it's an office building. The imposing Romanesque exterior has thick masonry walls, but the inside is surprisingly open and airy, thanks to an innovative use of iron framing. The building is essentially a square built around an open interior court that rises the full height of the building's 11 stories. Walk upstairs and follow the staircase to get a glimpse of the Rookery's interior courtyard and the sublime stairway spiraling upward.

Continue south along LaSalle Street. At Jackson Boulevard, the street appears to dead-end at the:

9. Chicago Board of Trade

The city's temple to high finance, this building houses the city's commodities exchange, an echo of the days when corn and wheat from the prairie passed through Chicago on its way east. Opened in 1930, the setbacks on the upper stories are typical of the Art Deco styling of the era, as are the geometric decorative elements over the entrance. Along the building's rear (southern) wall, a 24-story postmodern addition by Helmut Jahn repeats the original's pyramid-shaped roof, maintaining the symmetry between old and new. When it was built, the 45-story Board of Trade was considered so tall that the aluminum sculpture of Ceres, the Roman goddess of architecture who adorns the building's peak, was left faceless, because the builders figured no one in neighboring buildings would ever be high enough to see it.

Head 2 blocks east along Jackson Boulevard to the southwest corner of Dearborn Street and Jackson Boulevard. At 53 W. Jackson Blvd. is the:

10. Monadnock Building

This mass of stonework forms two office buildings that occupy an entire narrow block all the way to Van Buren Street. Only 2 years separate the construction of these architectural twins, but they are light-years apart in design and engineering. (You'll need to step across Dearborn Street to fully appreciate the differences.)

Monadnock I, on the northern end, was built by the architectural firm of Burnham and Root between 1889 and 1891. To support a building of this size at the time, the masonry walls had to be built 6 to 8 feet thick (note the deeply recessed windows at street level). Monadnock II, on the southern wing, was built by Holabird & Roche in 1893. Here steel framing was used, allowing the lower walls to be significantly narrower. The second building may have been an engineering marvel at the time, but the original Monadnock has a certain gravitas that the later addition lacks.

Walk south along Dearborn Street until you reach Congress Parkway. At 431 S. Dearborn St. you'll find the:

11. Manhattan Building

Constructed in 1891 by William Le Baron Jenny, this broad structure was viewed as an architectural wonder by many who visited Chicago during the Columbian Exposition 2 years later. To some, the eclectic use of materials and varied design of the facade give the Manhattan Building an appearance of complete chaos; others see a dynamic rhythm in the architect's choices. Today this former office building has been converted into condos.

From the corner of Dearborn and Van Buren streets, look a few blocks west along Van Buren until you spot a triangular tower, carved with slivers of window. That building is the Metropolitan Correctional Center, a 27-story jail for defendants preparing for trial in federal court downtown. The building's three-sided design derives from an attempt by the U.S. Bureau of Prisons to reform prison conditions: Cells were built along the edges surrounding a central lounge area. But it's still not a great place to hang out: To foil jailbreaks, the windows are only 5 inches wide (and have bars, to boot); although there's a recreation yard on the roof, it's enclosed on the sides and topped with wire mesh.

Walk 2 blocks east along Congress Parkway until you reach State Street. Turn left (north) to reach the entrance of the:

12. Harold Washington Library Center

This block-long behemoth, named for the city's first African-American mayor, is the world's largest municipal library. Designed by a firm led by Thomas Beeby, then dean of Yale University's School of Architecture, and completed in 1991, it self-consciously echoes the city's original grand buildings, such as the Auditorium Theater a few blocks east. Many Chicagoans think the place looks more like a fortress than a welcoming library -- but judge for yourself. The Winter Garden on the ninth floor -- a lovely retreat drenched with natural light -- is a good place to relax at the end of your walking tour.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.