Mauer is a village in south western Germany. It is located between Heidelberg and Sinsheim in the Rhein-Neckar district in the state of Baden-Württemberg.
Mauer is the location where the first remains of Homo heidelbergensis were found. The remains, a jaw, were discovered in 1907 in the local sand quarry by Daniel Hartmann, a worker there. The sandpit remained active for some time, and the original resting place of the remains no longer exists. However, the sandpit is now a nature park, and the sedimentary layers corresponding to those of the original find can be viewed on a 25 meter high section.