English: Built in 1886-1888, this Chicago School and Romanesque Revival-style building was designed by Daniel H. Burnham and John Wellborn Root of Burnham and Root to serve as an office building, and was named for a temporary two-story brick structure that previously stood on the site, which served as the Chicago City Hall and Chicago Public Library after the 1871 Great Chicago Fire, and was built in and around a metal water tank that had survived the fire. The Rookery Building utilized exterior load-bearing masonry walls and a steel internal structure in its construction, making it a hybrid of both the older construction method and a more modern method, and stands 12 stories and 181 feet (55 meters) tall, making it the oldest still-standing skyscraper in Chicago. It was renovated multiple times during its history, with a renovation by Frank Lloyd Wright in 1905-1907 refreshing the interior atrium and lobbies, lightening the dark cast iron and wood elements and cladding the columns and walls in white Carrara marble with gilded reliefs, adding the present chandeliers and urns in the space, and painting the metal roof structure white. A subsequent renovation in 1931 was carried out under the direction of William Drummond, a former Wright associate, whom added Art Deco elements to the interior, including new brass elevators and light fixtures, and modernizing the nearly half-century-old building to more contemporary tastes and standards, allowing it to compete more easily with newer nearby office buildings to attract new tenants.

The building’s exterior is clad in brick with a rusticated brown sandstone base, with large sandstone piers at the corners and middle bays, engaged cylindrical red marble columns between the bay windows on the first and second floors, with decorative carved stone surrounds at the arched entrance bays on the LaSalle Street and Adams Street facades, which feature brass doors, and iron and glass curtain walls on the Quincy Street and Rookery Court facades. Above the second floor, the building is clad in brick with terra cotta trim, one-over-one double-hung windows, ornate terra cotta street signs at the corners of the third floor facade, decorative recessed spandrel panel and belt coursing, projected bays above the entrances with decorative trim surrounds, arched window bays on the seventh and tenth floors, a parapet enclosing a low-slope roof, an obscured twelfth floor penthouse, decorative carved reliefs, a hipped glass roof over the central light court, and semi-circular balconies with terra cotta and iron railings and decorative corbels. Inside, the building features lobbies at the Adams Street and LaSalle Street entrances with Carrara Marble walls with decorative gilded reliefs, Carrara marble urns at the staircases, mosaic tile floors, urns, coffered ceilings, decorative light fixtures, and Frank Lloyd Wright-designed light fixtures. The center of the first and second floor is home to a large atrium with Carrara Marble walls and column surrounds with gilded reliefs, a single panel of a column surround that has been removed to reveal the original ornate ironwork underneath, a mosaic tile floor, iron railings and staircases, Frank Lloyd Wright-designed chandeliers, a white-painted iron structure supporting a large glass roof, a balcony ringing the second floor, large plate glass storefronts on the first and second floor, Carrara marble urns and octagonal posts at the base of the stairwell, and a large iron Oriel staircase that climbs through the building and features curved flights of stairs and an iron railing, opening onto elevator lobbies on each floor. The elevator lobbies on the lower floors feature brass doors with geometric motifs and sconce fixtures, mosaic tile floors, vaulted ceilings with decorative trim, and Carrara marble walls.

The building was listed on the National Register of Historic Places in 1970, was designated a Chicago Landmark in 1972, and was designated a National Historic Landmark in 1975. The building is a contributing structure in the West Loop–LaSalle Street Historic District, listed on the National Register of Historic Places in 2013. The building underwent a rehabilitation in 1992, restoring the exterior to its original Burnham and Root design, and restoring the interior lobbies and atrium to their Frank Lloyd Wright and William Drummond designs. The building received a LEED Gold certification in 2014, and was renovated between 2015 and 2017 to modernize building systems and facilities, including restrooms and elevators. The building remains in use as an office building, with retail space on the first floor, including a Frank Lloyd Wright Trust gift shop in the atrium. The building is the oldest of several structures along LaSalle Street that form a historic Skyscraper “Canyon” that terminates at the tallest structure along the street, the Board of Trade Building.