[2] It contains the Millennium Monument, a nearly full-sized replica of the semicircle of paired Roman Doric-style columns (called a peristyle) that originally sat in this area of Grant Park, near Michigan Avenue and Randolph Street, between 1917 and 1953.

Lying between Lake Michigan to the east and the Loop to the west, Grant Park has been Chicago's front yard since the mid 19th century.

Landscape architect Kathryn Gustafson designed 14 new 320-pound (145.1 kg), aluminum "Maggie benches" in Millennium Park, mostly in Wrigley square, in honor of Mayor Daley's wife.

[9] An architectural model of Wrigley Square and Millennium Monument, designed by O'Donnell, Wicklund, Pigozzi and Peterson Architects, Inc. (OWP&P) in 2000, is on display at the Harold Washington Library Center.

[12] The pedestal of the peristyle is inscribed with the names of the 115 financial donors (including Oprah Winfrey) who made the 91 contributions of at least $1 million each to help pay for Millennium Park.

[2] The David Dillon and Michael Patrick Sullivan (of OWP&P) design is based on original drawings by Bennett found in the Chicago Park District's archive.

[10] Each of the limestone columns is cut from an Indiana quarry [18] and made of five 2,200 pounds (997.9 kg; 157.1 st) sections reinforced by steel rods and plates.

In addition, on the reverse side in approximately the same location, the monument has a special plaque commemorating John H. Bryan's contribution as the head of fundraising for the Park.

[20] The monument, despite being relatively small in comparison to the rest of Grant Park, makes its presence known as the central focus to shape Wrigley Square and the surrounding landscape.