Irwin is an unincorporated community

Unincorporated area

In law, an unincorporated area is a region of land that is not a part of any municipality.To "incorporate" in this context means to form a municipal corporation, a city, town, or village with its own government. An unincorporated community is usually not subject to or taxed by a municipal government...

 in southwestern Union Township

Union Township, Union County, Ohio

Union Township is one of the fourteen townships of Union County, Ohio, United States. The 2000 census found 1,565 people in the township, 939 of whom lived in the unincorporated portions of the township.-Geography:...

, Union County

Union County, Ohio

Union County is a county located in the US state of Ohio. As of the 2010 census, the population was 52,300. Increasingly becoming more of a suburban county, the population was estimated at 47,234 in 2007 by the U.S. Census Bureau...

, Ohio

Ohio

Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...

, United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. It is located at 40°07′21"N 83°29′22"W, at the intersection of Ohio State Route 4 and 161.

The Irwin Post Office was established on 15 May 1858, and serves the surrounding area, including the community of Rosedale

Rosedale, Ohio

Rosedale is an unincorporated community in central Pike Township, Madison County, Ohio, United States, and roughly thirty miles west of the city of Columbus. The ZIP code is 43029 and mail is currently delivered by the Irwin post office....

.

Located near Irwin is Elmwood Place

Elmwood Place (Irwin, Ohio)

Elmwood Place is a historic farmstead in the southwestern corner of Union County, Ohio, United States. Located along State Route 161 near the community of Irwin, the farmstead comprises six different buildings spread out over an area of ....

, a historic farm that is listed on the National Register of Historic Places

National Register of Historic Places

The National Register of Historic Places is the United States government's official list of districts, sites, buildings, structures, and objects deemed worthy of preservation...

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