On Episode 43, Aaron Holley — an Antietam Institute board member and West Virginia University graduate — talks with co-hosts John Banks and Tom McMillan about fields of fire, lost roads, hidden fence lines and other information derived from his fascinating battlefield mapmaking.

Holley took the late 19th-century Ezra Carman-Emmor Cope Antietam maps and aligned them with locations on today's battlefield. Through remote and field-based work, dozens of locations were matched between those maps and actual locations on the ground. This process gives these classic maps a modern GPS usage while preserving their timeless aesthetic.

Per the Antietam Institute, "Both the base map and the Carmen-Cope maps are available to purchase and download to your phone through the Avenza app. Peruse the map on and off the field, and by using GPS, you can immerse yourself on the landscape of the battlefield. Simply download Avenza to your smartphone, create a free account and purchase this map set for only $14.99."

The podcast is sponsored by Civil War Trails, which since 1994 has connected visitors with small towns and big stories across a network that now spans six states.

Join McMillan and Banks for regular podcasts about Antietam, the Maryland Campaign and the Civil War — the most compelling period in American history.

McMillan is author of the recently released The Year That Made America: From Rebellion to Independence and four other books. Banks is author of A Civil War Road Trip Of A Lifetime and numerous magazine articles about the Civil War. Find them on Facebook at Author Tom McMillan and John Banks' Civil War Blog. Banks' popular Civil War blog is here.