NGP Standards and Specifications

Historical Topographic Map Collection


The Historical Topographic Map Collection (HTMC) is a digital archive of about 190,000 printed topographic quadrangle maps published by the U.S. Geological Survey (USGS) from the inception of the topographic mapping program in 1884 until the last paper topographic map using lithographic printing technology was published in 2006.


The HTMC Standard defines the HTMC digital map product.

The HTMC Specification defines the detailed requirements for producing, archiving and disseminating the HTMC digital collection of printed topographic quadrangle maps.


For comments or questions about the HTMC Standard or HTMC Specification documents, please email: