Is Colorado a perfect rectangle? The map of Colorado’s border deviations below.
The borders of Colorado were fixed in 1850. Colorado’s borders were originally defined to be lines of latitude and longitude, making its shape a latitude-longitude quadrangle which stretches from 37° N to 41° N latitude, and from 102.05° W to 109. 05° W longitude. On the northern side, the border is shorter than the southern one because circles of latitude get shorter as they get farther from the equator and closer to the poles. Colorado, Wyoming, and Utah are the only U.S. states that have boundaries defined solely by latitude and longitude lines.
Iowa is the only U.S. state whose eastern and western borders are entirely rivers.