Determining the Age of GLO-mapped Trail Networks

Map of Upper Iowa

Publication: Midcontinental Journal of Archaeology, Vol. 40, No. 2

Author: William E. Whittaker

Date of Publication: 2015

PDF File: Whittaker-2015-Determining-the-Age-of-GLO-mapped-Trail-Networks.pdf



Between 1833 and 1861, the Government Land Office (GLO) mapped almost 11,000 km of trails in Iowa. It is unknown if substantial portions of this GLO-mapped trail system predate the arrival of Euro-Americans; it is possible they were established in prehistory and used into the historical period. This Geographical Information Systems study compares a sample of archaeological sites within 1 km of the GLO trails in northern Iowa with a control sample. It was expected that GLO trails would be more common near Late Prehistoric sites if much of the GLO trail system was established before Euro-American arrival. Analysis indicates a relationship between GLO-mapped trails and Late Prehistoric, early historic Indian, and early historic Euro-American sites. Statistically, the connection between GLO trails and early historic Euro-American sites is by far the strongest; however, biases in the data suggest the association between Late Prehistoric and early historic Indian sites and GLO trails is underestimated.