Thousands of people pass by the Keokuk Lock and Dam and power plant everyday.
A group called the Mississippi River Power 100 is getting ready to celebrate the 100th anniversary of construction of that structure.
The anniversary includes a four-day festival which starts on June 27th and it will be full of history, tours and trolleys.
"You know, as my shirt says, it was America's first great dam. It was a big thing when it was built, besides it went clear across the Mississippi River, nothing else had. A lot of engineers said it couldn't be done but, of course, Hugh Cooper did it. And it's been setting here for 100 years doing it's job," Mike Foley, a member of the anniversary committee said.
Larry Weiman is the power plant superintendent for Ameren Missouri. He's worked at the plant for the past 30 years. He said it's like working in a real-life museum. There's even some equipment inside the plant still operating since the day the plant went online 100 years ago.
"You know, to take on a project, where you have four or five or six things that's never been done? I think that's amazing," Weiman said.
Visitors will be able to visit the power plant museum display at the River City Mall. They also can sign up for an actual tour of the power plant and take a ride on the trolley. This will be one of the few times the dam will be open to the public and available for tours ... just in time to celebrate the 100-year milestone.