A little later than expected, Chicago’s third observatory is coming into view as the owner of the Aon Center prepares to start building the long-discussed $185 million addition.

The skyscraper’s owner, 601W Cos., expects to begin construction on the yet-to-be-named observation deck overlooking Millennium Park in the third quarter of this year, said Aon Center general manager Matthew Amato.

The tourist attraction is expected to open in spring 2022, he said.

That opening date is about a year and a half later than the one 601W cited in December 2018, as the project neared zoning approval from the city.

Since that time, 601W has finalized a deal with another New York-based firm, Legends, to run the observatory.

“The 20-year agreement took a long time to negotiate, but now we’re excited to get going on it,” Amato said.

Legends also formed a joint venture with 601W to share ownership of the observatory, Amato said.

Legends operates facilities and provides concessions and other services to many well-known sports venues and tourist attractions, including the One World Trade Center’s observatory, Yankee Stadium and the Rose Bowl.

The venture is now in talks for construction financing to pay for the observatory addition, Amato said.

The two-level space will include a restaurant, bar, event space and virtual reality experiences. The main attraction will be a thrill ride called the Sky Summit, which will lift enclosed cabs filled with visitors over the building’s edge for 30 to 40 seconds.

Work is expected to occur simultaneously on several aspects of the project, including adding a glass elevator tower to the exterior of the building at 200 E. Randolph St., Amato said.

There also will be a 9,000-square-foot pavilion built on the southeast side of the property for guests to enter, and a walkway built underneath the office tower leading to observatory elevators on the northwest side.

Atop the Aon Center, space formerly used for mechanical systems on the 82nd floor will be converted into an observatory with views of the park, Lake Michigan and the skyline. A partial 83rd floor will provide an area for visitors to enter the thrill ride.

The Aon Center, completed in 1973 and previously known as the Standard Oil Building and the Amoco Building, is Chicago’s third-tallest skyscraper.

At 1,136 feet tall, it trails only Willis Tower (1,451 feet) and Trump International Hotel & Tower (1,389 feet). When it’s completed nearby this fall, 1,191-foot-tall Vista Tower will knock the Aon Center down to No. 4 on Chicago’s tallest buildings list.

When the Aon Center addition is complete, Chicago will join New York as the only American city with three observatories. Chicago’s others are Skydeck Chicago in Willis Tower and 360 Chicago in the former John Hancock Center on North Michigan Avenue.

The Aon Center’s owner, whose other Chicago projects include The Old Post Office redevelopment, estimates its new observatory will generate $30 million to $40 million in annual revenue. 601W bought the Aon Center for $712 million in 2015.

The Tribune in February 2018 first reported that 601W was looking into adding the glassy exterior elevator tower to help create an observatory, and in May 2018 the landlord publicly disclosed its plans.

Soon, the area just north of Millennium Park will be a construction zone. Across the street from the Aon Center, an affiliate of Chicago-based CA Ventures is about to begin construction of a 46-story apartment tower on a vacant lot at 222 N. Stetson Ave.

Published by the Chicago Tribune 


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