Electorate of Cologne; the keys refer to St. Peter the patron saint of the Archbishopric of Trier (and of the cathedral of Trier), of which Andernach formed part. The red (key) colour adverts to the red cross (on silver) in the coat of arms of the Electorate of Trier. The oldest town seal shows St. Mary sitting on a throne with a church in her right hand and with the left hand holding a town. The seal inscription says: MATER DEI PATRONA CIVIUM ANDERNACENSIUM – Mother of God, patron saint of the Andernachian citizens. The oldest seal was made before 1200, the oldest seal impression dates from the year 1250. Description Founded by the Romans as Antunnacum in 12 BC on the site of an old Celtic settlement probably called Antunnuac, Andernach is one of the oldest towns in Germany which as such held its "Bimillenary feast" in 1988. Both the Roman and the Celtic names mean "village or farm of Antunnos/us"—a man not yet identified. It was the southernmost outpost of the Electorate of Cologne from the 12th to the 19th century. In addition to the touristically appealing medieval remnants of the old town fortifications, the city of Andernach is the location of several old industrial plants such as a huge malt mill (the last one of more than ten mills and breweries from the 19th and 20th centuries dismantled in 2008). In the 19th century the town was noted for the production of millstones, bricks and clay for making tobacco pipes. Among the more modern of its industrial / manufacturing base is a large steel-mill to produce cold formed tin plate and companies manufacturing medicinal products, raw food materials, cast iron products, engines and engine parts. Tourists who come to the region usually visit the medieval fortifications such as the tall "Round Tower" (Ger. "Der Runde Turm") finished in 1453, the archiepiscopal (Electorate of Cologne) castle ruins with a well-preserved keep, and the remains of the town wall with several well-restored wall towers and two gates: the "Rhine Gate" (das "Rheintor") built around 1200 as the "Grain Gate" (die "Kornpforte"; last renovation and reconstruction in 1899 after 17th century plans) and the "Coblencian Gate" ("Koblenzer Tor"), originally called the "Castle Gate" ("Burgpforte"); in medieval and Renaissance times up to the 19th century the German word "Pforte" (from Latin "porta") was used for town and church gates instead of