The Teutoburg Forest and the Egge Hills stretch across the region and form the frontier to the Westphalian Lowland. Eastern Westphalia–Lippe is one of the supposed regions of the Battle of the Teutoburg Forest in the year 9 AD, where an alliance of Germanic tribes defeated a Roman army. In 1875, a statue was unveiled of the commander Arminius, who led the Germanics to victory at the battle. This statue, the Hermannsdenkmal, is one of the best-known sights and landmarks in Ostwestfalen-Lippe.