Of 102 counties in the Land of Lincoln, Knox County ranks 23rd by size (719 square miles). Knox County is in Western Illinois. Recent listings of lakefront homes and property for sale in Knox County, Illinois, totals about 1,000 acres and a combined market value of nearly $7 million. The most common type of land for sale by combined acreage in Knox County is undeveloped land. Browse all waterfront property for sale in Knox County on the Land Network to find the marina, lakefront and other recreational property that meets your needs, from waterside land perfect as a retirement investment to existing residential waterfront land and property for hunting, fishing and other outdoor-recreation pursuits! The most common type of land for sale by combined acreage in Knox County is undeveloped land.