Geographic Center of the Contiguous United States

One of the locations claimed to be the Geographic Center of the Contiguous (or Conterminous) United States is pinpointed by a historical marker that is located within a small park near the town of Lebanon, Kansas. It is located at the intersection of AA Road and 191 Road, accessible by a turn-off from US Hwy 281 approximately a mile north of the town. In actuality, the measured center is about 1/2 to 3/4 mile away on a private farm, but the owner did not want tourists trudging through his field, so the marker was placed as close as possible. There is generally an American flag flying on the pole placed on top of the monument. Just to the south of the monument, yards away, exists a covered picnic area and small four-pew chapel where a couple can take wedding vows if they wish.

The reality of the monument is probably a little more fiction than fact. In 1918, the Coast and Geodetic Survey found this "center" by balancing on a point a cardboard cutout shaped like the U.S. Thus, measured in this manner, the actual "center" of the U.S. could be located twenty or more miles from this point, but still might not pinpoint the true "center" at all as an official measurement would have to be defined by an agreed upon standard which does not exist.

The plaque's inscription

The GEOGRAPHIC CENTER of the UNITED STATES
LAT. 39°50' LONG. 98°35'
NE 1/4 - SE 1/4 - S32 - T2S - R11W
Located by L.T. Hagadorn of Paulette & Wilson - Engineers and L.A. Beardslee - County Engineer. From data furnished by U.S. Coast and Geodetic Survey.
miSponsored by Lebanon Hub Club. Lebanon, Kansas. April 25, 1940.

Methods of calculation

In contrast to the complicated centroid method, a simplified method of mathematically determining the geographic center of the United States is to calculate the coordinates for the point halfway between the northernmost and southernmost and the easternmost and westernmost points of the contiguous U.S. The result is about 8.5 miles southeast of Grenola, KS at 37°15'2" N and 96°21'30" W.

This is using Ballast Key, Florida (24°31′15″N) as the southernmost point, Northwest Angle, Minnesota (49°23'4.1"N) as the northermost point, West Quoddy Head, Maine (66°57'W) as the easternmost point, and Bodelteh Islands, offshore from Cape Alava, Washington (124°46'W) as the westernmost point.

ee also

*Geographic centers of the United States
*Mean center of U.S. population
*centroid
*Extreme points of the United States

External links and references

* [http://www.apprendre-en-ligne.net/blog/docu/centerus.pdf The Center of the United States] article about applying mathematical methods to geography
* [http://www.kansastravel.org/geographicalcenter.htm Kansas Travel] article
* [http://www.clui.org/clui_4_1/lotl/lotlsp99/geo.html Center for Land Use Interpretation] article about the origins and accuracy of the marker
* [http://www.roadsideamerica.com/roger/QueryTips.php3?tip_AttractionName=center&tip_Town=&tip_State=KS&Submit=Go+Roger! Roadside America] article
* [http://erg.usgs.gov/isb/pubs/booklets/elvadist/elvadist.html#Geographic%20Centers USGS information]
* [http://www.kansasphototour.com/center.htm Kansas Photo Tour]
* [http://www.nytimes.com/2008/06/02/us/02land.html?pagewanted=all New York Times ]