Former US President Barack Obama and former first lady Michelle Obama are greeted by City of Chicago Mayor Rahm Emanuel during a community event on the Obama Presidential Centre at the South Shore Cultural Centre in Chicago, Illinois, US, May 3, 2017. [Photo/Agencies]

CHICAGO - Former US President Barack Obama returned to Chicago on Wednesday to unveiled a 3-D model of his presidential center which includes three buildings.

Obama and his wife Michelle Obama made their first public appearance on plans for the presidential library at the South Shore Cultural Center of south Chicago. Hundreds of people attended the invite-only event where newly released renderings were on display for viewing.

The renderings shown propose a large stone structure half-sunken into Jackson Park. Obama said the center will take four years to build and will bring thousands of jobs both in construction of the center and at the library. It should attract about 700,000 visitors a year.

"Though we had a formal bidding process to determine where the presidential library would be, the fact of the matter was it had to be right here on the South Side," Obama said.

The design includes three buildings, a museum, a forum and the library itself, along with a sprawling public plaza. This area will be open to the public and the center will include indoor and outdoor spaces.

"It's going to be a transformational opportunity for this community," Obama said. "It's not just a building, it's not just a park but hopefully this ends up being a hub that all of us can see a brighter future for the South Side."

He also stressed that the center aims to train young people and cultivate their leadership in their communities.

The design was crafted by Tod Williams and Billie Tsien, the husband-wife New York architects who were also in attendance.

According to Obama Foundation, the three buildings could encompass 200,000 to 225,000 square feet (18,500 to 23,200 square meters). That would be roughly the same size, or slightly larger, than the George W. Bush Presidential Center in Dallas.

Construction is estimated to be at least 500 million US dollars. The former president will fundraise to cover that cost. If all goes according to plan, the center would open in 2021.