Within the campus of University of Wisconsin-Milwaukee is a geographer’s treasure trove: over a million artifacts from the American Geographical Society, one of the most incredible collections of maps, atlases and globes to be found in America.

But, ironically, the library is practically unexplored territory. When I asked for directions on campus many students themselves didn’t know it was there.

Inside The Most Amazing Map Library That You’ve Never Heard Of | Atlas Obscura.