A mansion on the real estate market in Alton, Illinois, for $8.45 million has an underground tunnel that’s cool, chic, and sophisticated. Larry McMillian Jameson Sotheby’s International Realty ...

Illinois, for $8.45 million. The massive nine-bedroom, 9.5-plus-bathroom megamansion has an enchanting allure throughout the interior and is graced with style. Called the Olin Mansion (after the ...