Where is Four Corners, really?

I visited the Four Corners monument on a family vacation in 2004, then again in October 2010.  It's not much to see - you pay three dollars per person to take your picture at a very ostentatious monument that's located on Navajo tribal land.  (Not until after the second visit did I discover the joys of frybread.)  This place is in the middle of nowhere.  Really, I mean it.

The middle of Nowhere (actually a nice place to visit)

Since the 2004 trip, I had heard rumors that the monument was actually misplaced when initial surveying was done in the 19th century. When Paul and I were driving through the area last October, my GPS placed the monument squarely in New Mexico.  As I was doing some of my geography reading a few weeks ago, Four Corners flashed into my mind.

Since Earth has a very irregular shape, geodicists (people who study the Earth's shape) create models called ellipsoids to make calculating geographic locations easier.  When a new ellipsoid called GRS 80 replaced the previously-used Clarke 1866 ellipsoid, the geographic coordinates for specific locations changed, usually between 10 and 100 meters.  But when I thought a little harder, I realized that this would in no way explain the supposed 2.5 mile discrepancy in the location of Four Corners.  So I did a google search, and found this article from the National Geodetic Survey (NGS), vehemently defending the accurate location of the monument.

I searched for the geographic coordinates, converted them to decimal degrees, and created the Mercator projection below showing the location of Four Corners.

Penn State Oneline GIS Education, 2011.

Next I checked google maps:

And there it is - right where it's supposed to be!  I suppose I really should believe the NGS after all.  And I suppose that means that even though Paul and I did not take any epic hail-showering voyages through Utah, he has, in fact, set foot in the state.  Or at least, on sovereign tribal land that just happens to fall in the state of Utah...

Oh Paul.  You would.