Looking for historic county plat maps of Colorado.

[Route66Fan]

I am trying to map out the "Pike's Peak Ocean to Ocean Highway" in Colorado & would like to know where I can find historic plat maps of Colorado. The county that I am currently mapping out the route in is Park County, CO. I've checked Historic Map Works & they do not have any historic plat maps of Park County, CO. They do have one for Chaffee County, CO, but it is from 1976 & I am looking for county plat maps from the late 1800's to 1920's. Please help. Thank you.

[WillWeaverRVA]

Have you checked this thread?

[Route66Fan]

Have you checked this thread?

I've checked the thread & there aren't any historic Colorado county plat maps.

[usends]

The Denver Public Library has a good map collection, and they may have what you're looking for, but I don't know if you're going to find much online.  Closest thing I can think of would be the 1930s county maps used in the 1940 Census for their basemaps, available here.