Archaeologists say they've identified the oldest known Roman military fortress in Germany, likely built to house thousands of troops during Julius Caesar's conquest of Gaul in the late 50s B.C. Broken bits of Roman soldiers' sandals helped lead to the discovery.

Researchers knew about the large site — close to the German town of Hermeskeil, near the French border — since the 19th century but lacked solid evidence about what it was. Parts of the fort also had been covered up or destroyed by agricultural development.

"Some remains of the wall are still preserved in the forest, but it hadn't been possible to prove that this was indeed a Roman military camp as archaeologists and local historians had long suspected," researcher Sabine Hornung, of Johannes Gutenberg University of Mainz (JGU), said in a statement....