The geographic center of the United States has been a long-contested metric. Finding the geographic center of a city, country, or continent is challenging because there are a variety of ways to go about calculating this geographic place. Some geographers add in bodies of water to their geographic calculations, while others choose to leave out bodies of water or islands.
The U.S. Geological Survey recognized the complexities of determining geographic centers and said that there was no one way to calculate this center. Back in 1964 the agency published a report on the centers of states, noting “There is no generally accepted definition of geographic center, and no completely satisfactory method for determining it.”
For Peter Rogerson, PhD, at the University of Buffalo, this challenge wasn’t a reason why he wasn’t going to try to find the best way of calculating the geographic center of each of the states of the United States.
Rogerson published a paper in 2015 in The Professional Geographer describing his new approach to finding the center of a spatial entity. He used his method to pinpoint the center of the 48 contiguous United States stating:
The geographic center of the contiguous forty-eight states (plus the District of Columbia) is at 39.8355 N, 99.0909 W. This location in Kansas is 5.3 miles from Agra and 5.5 miles from Kensington, at the intersection of East 1300 Road and East Mohawk Road. It lies 29.5 great circle miles west of the long-standing designated center of Lebanon, Kansas.
Finding the geographic center of a spatial entity might seem like a fool’s errand, but the theoretical center of a state or city used to be how people chose where their seat of political power would be. Most people seem to be interested in the center of their city or state as a point of interest, or as another landmark that makes the geographical area around them special.
More technically complex than using a cardboard cutout that that the USGS employed in the 1960s, Rogerson’s new method takes into consideration the curvature of the Earth when assessing a geographic center. Rogerson utilized the azimuthal equidistance map projection in his equations.
Interactive Map Showing the Geographic Center of Each State
In calculating the geographic center of each state, Rogerson factored in both land and interior waters (like lakes), as well as islands. The geographic center for each state are pinpointed in this interactive map. Simply click on each point to see the calculated geographic center as well as a comparison to the USGS and US Census calculated geographic centers.
Rogerson, P. A. (2015). A New Method for Finding Geographic Centers, with Application to US States. The Professional Geographer, 67(4), 686-694.