About a mile south of the O’Hare Oasis on the Tri-State Tollway, a billboard trumpets, “King Wanted.” It’s part of Paul Iwanski’s marketing campaign to sell the 18,000-square-foot castle he is building on a one-acre lot in Oak Brook.

Iwanski is a partner in Iwanski-Pyzik Masonry, a Schaumburg company that specializes in building public schools; its current and recent projects are in Wheaton, Willowbrook, Sycamore, and Coal City. Iwanski confesses that he always dreamed of building a castle, since seeing Wawel Castle in his native Poland. So a couple of years ago, he paid $800,000 for a lot near the intersection of York Road and 31st Street in Oak Brook.

Iwanski’s partner in the company, Mark Pyzik, signed on, and they lined up a few investors (whom they won’t identify) to back the project. Priced at $5.7 million, the castle is slated to be finished in about six months. Click through my photo tour to learn more about the castle and Iwanski’s Plan B in case he can’t sell it anytime soon.