One of the earliest maps of Colorado published in Denver.
Thayer was one of the earliest map publishers in Colorado and without question the most active during the period. He initially published a Colorado map with Rufus Blanchard in Chicago in 1870-71, before relocating production to Denver.
The present map was first offered in 1873. In 1875 (Sixth Edition), the was issued for the first time with the land districts of Colorado overprinted and named in red.
The map is hand colored by counties, and shows the extent of the township surveys, railroads, early mining regions, etc. A number of the western towns are beginning to appear on the map.
A near flawless example of this scarce map.
Not in the Denver Public Library or Library of Congress. Pocket map, lacking front cover, but w/back printed wrap.