The Pritzker Pavillion in Millenium Park (Image: OutofChicago.com CC by/nc/sa)

By Lee BayStand for a moment on the southwest corner of Wacker and Wabash, where the Main Branch of the Chicago River defines the northern edge of downtown.

Look around a bit. Nearly a century of Chicago’s best architecture can be seen with just the sweep of the eye. And much of it is internationally famous.

Trump Tower stands on the northeast corner of the intersection. At 1,389 feet, the four-year-old glass giant rises above the river as the city’s second-tallest building (and the 11th tallest building in the world). It’s a nicely done building that is surprisingly subtle: the beauty comes from curves, the way it mirrors the sky and complements the riverfront.

Lit for the holidays: Center left, the Wrigley Building. Center right, the Tribune Tower. Between them, the John Hancock Center. (Image: Brian Koprowski CC by/nc/sa)

Glance to the right, toward Michigan Avenue, and there’s the Wrigley Building – an architectural wedding cake clad in terra cotta – completed in 1924. The Gothic Revival headquarters of the Chicago Tribune sits across the street from the Wrigley. The two towers provide a visual gateway to the famed Magnificent Mile shopping district on North Michigan Avenue.

Perhaps more than any other American city, Chicago has used architecture to express its identity and assert itself – and, when need be, reassert itself – on the world stage. The metropolis’s sense of itself as a world-class city is based as much in its architecture as in its internationally-recognized financial markets, theater, celebrities, or universities.

That was the case in 1893, when the World’s Columbian Exposition opened on stunningly beautiful grounds on the south lakefront, and in the 1960s and early ’70s, when bold new skyscrapers such as the Sears Tower (now the Willis Tower) and the John Hancock Center revitalized the Loop and neighboring Streeterville. And it certainly informed downtown’s masterful Millennium Park, which opened to great fanfare and world notice nearly a decade ago.

So here are five architecturally significant buildings and sites that embody Chicago and contribute to the city’s global presence.

The Willis Tower (formerly the Sears Tower) was the tallest building the world until 1998. (Image: Justin Kern CC by/sa/nc)

Willis Tower, 223 S. Wacker (1973).

The world’s tallest building until 1998, the former Sears Tower still cuts an impressive figure in the West Loop. Composed of nine sections stacked and bundled together, the brawny and powerful-looking 1,450-foot tower architecturally embodies the “City of Broad Shoulders” romanticized by Carl Sandburg. Designed by Skidmore Owings & Merrill, the black steel-and-glass structure is still the tallest building in the Western Hemisphere (until New York’s One World Trade Center is completed next year). Willis Tower might very well make a global splash again if its owners can pull off a plan to paint the building silver and equip it with a host of energy-saving retrofits that would allow the tower to run on 20 percent of the power it currently uses.

Apart from the striking visuals, architect Bertrand Goldberg’s vision for the “River City” complex included skybridges, schools and a mix of residential and retail. (Image: ChicagoGeek CC by/sa)

Marina City, 300 N. State (1959-1967).

Designed by visionary Chicago architect Bertrand Goldberg, Marina City contains a hotel, restaurants, a bowling alley, the House of Blues, and other amenities. But the complex’s best-known features are its twin cylindrical residential towers, 588 feet high, which are as much a part of the city’s identity as are the blues and deep dish pizza.

At 25 acres, Millennium Park is the world’s largest green roof, covering two parking garages, a commuter railway and an opera house. (Image: Ian Freimuth CC by/sa/nc)

Millennium Park (2004).

Built over an active commuter railway, this 24-acre addition to downtown’s Grant Park has become a great civic gathering space. In warm weather, crowds flock to performances at a concert bandshell and walk a serpentine footbridge, both designed by architect Frank Gehry. They gaze at themselves and the city reflected in “Cloud Gate,” the sleek, mirrored stainless-steel sculpture—Chicagoans playfully nicknamed it “The Bean”—by celebrated British artist Anish Kapoor. And they frolic in Crown Fountain, designed by Jaume Plensa , with water cascading into a reflecting pool from a pair of five-story glass brick towers with LED screens that project a changing rotation of faces. The park has become a must-see for international visitors. And city planners from across the country and the world have studied the park’s ability to bring foot traffic, retail and residential development to a section of Michigan Avenue that had been a virtual dead zone.

Ludwig Mies van der Rohe designed the building to suit his famous chairs. 880 Lakeshore’s wide open first level spills out towards the street, a style that is now a de facto standard for corporate lobbies. (Image: janmikuey CC by/nc)

860-880 Lake Shore Drive (1951).

The twin towers – a pair of upturned and minimalist glass boxes positioned on a wide plaza – created an architectural style that would be replicated in thousands of office and residential buildings around the world. Designed by Ludwig Mies van der Rohe, the 26-story buildings look as crisp today as they did a half-century ago, courtesy of a recent multi-million-dollar rehab that included repainting their black exteriors and restoring the travertine plaza on which both towers sit.

Aqua Tower by Jeanne Gang (Image: joevare CC by/sa)

Aqua Tower, 225 N. Columbus (2010).

The sleek, 86-story concrete residential/hotel/office tower has won acclaim locally and internationally, in no small part due to its undulating balconies, which give the building a sculpted – almost biomorphic – look. Designed by Chicago architect Jeanne Gang and her firm Studio/Gang, the building has sustainable features such as rainwater collection, energy-conserving lighting and a green roof. The shape of the balconies are also a bow to sustainability, as they are designed to capture sunlight.

The architectural gallery continues downtown and across the city, with buildings designed over the course of 120 years by the most notable architects in the world. Mies van der Rohe. Frank Lloyd Wright. Louis Sullivan. Daniel Burnham. I.M. Pei. Eero Saarinen. Edward Durrell Stone. Adrian Smith. Frank Gehry. Renzo Piano. Even singer Dionne Warwick, who designed the interior spaces of the Black Ensemble Cultural Center, a theater that opened last year on the city’s North Side. Chicago is a city where design—along with politics, sports, and the often notorious weather—matters.