Osage County is in Wooded Hills Kansas. Of the 105 counties in the Jayhawk State, Osage County is 62nd in terms of its size (719 square miles). Browse all waterfront property for sale in Osage 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 Osage County is recreational property.