Carved out of timber and prairie and surrounded by fields of soybeans and corn, Monticello was founded in 1822 and named after Thomas Jefferson's Virginia estate. Monticello, a National Main Street Community, boasts an intriguing history as one of the "patent medicine capitals of the world" and features elegant streets full of wide-lawned mansions, such as State Street, nicknamed "Millionaires' Row." The impressive courthouse is ringed with brick buildings from the late 1800s. The Allerton estate, a 32,000-square-foot Georgian mansion on 12,000 acres along the Sangamon River, was donated to...