The park, which will take up the entire block between Fifth, Sixth, Jefferson and Madison streets, is scheduled to be completed by June.

It is the second park to occupy the site. The first was completed in the 1990s and had a popular ice skating rink in the winter and a farmers' market in the summer. It also became a haven for vagrants and homeless people who sometimes used rain-filled reflecting pools to wash clothes or themselves.

This time, officials hope the park will serve as a kind of front porch for the city and the Lincoln complex. The adjacent Union Station, a former railroad station and shopping complex that is being converted to a visitors' center, offices and meeting space, will be finished in 2007.

Julie Cellini, chairwoman of the Illinois Historic Preservation Agency's board, told about 40 people gathered for Wednesday's ground-breaking that she hoped to create beauty "in an area of Springfield that was once blighted."

Gov. Rod Blagojevich - whose scheduling required the event to be moved up about an hour - compared the park's importance to that of Millennium Park on the banks of Lake Michigan in Chicago, which hosts free concerts and has an amphitheater, just as Union Square Park will.

"I believe Union Square Park can be to Springfield what Millennium Park is to Chicago," Blagojevich said.

He noted that almost 350,000 people have visited the presidential museum since it opened in April.

"When we finish this park, I suspect more and more people will want to come here," the governor said. "It will be a place all of us will think about when we think of Springfield."

Besides the large, open-lawn amphitheater and a Victorian-style garden honoring Mary Todd Lincoln, Union Square Park will have benches, arbors, plantings and sidewalks to provide places where people can sit and relax.

"Nine months from now, this space will be filled with trees and flowers, but most important of all, with people," Cellini said. "People will get married in the gazebo. They will take photos in Mary Todd Lincoln's rose garden. They will sit on a bench next to a bronze sculpture of Abraham Lincoln."

White and Borgognoni Architects of Carbondale designed the park. BRH Builders of Springfield will be in charge of construction. B&B Electric of Springfield will do the electrical work.

The renovation of Union Station includes the re-creation of a 140-foot clock tower that has four working faces. The tower was an original element of the station but was removed in 1946. About 20 percent of the work on the station has been completed.

Chris Wetterich can be reached at 788-1523 or chris.wetterich@sj-r.com.