Of 92 counties in the Hoosier?State, Washington County ranks ninth in terms of size (516 square miles). Washington County is in South Indiana. There is about 1,000 acres of riverfront property for sale in Indiana's Washington County based on recent Land Network data. The combined market value of land for sale here is nearly $700,000. Browse all waterfront property for sale in Washington 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 Washington County is house.