The Roman geographer Pomponius Mela was the first to mention the lakes around 43 AD, calling the upper lake "Lacus Venetus" and the lower lake "Lacus Acronius", the Rhine passing through both. Around 75 AD, The naturalist Pliny the Elder called them both, "Lacus Raetiae Brigantinus" after the main Roman town on the lake, "Brigantium" (later Bregenz). This name is associated with the Celtic Brigantii who lived here, although it is not clear whether the place was named after the tribe or the inhabitants of the region were named after their main settlement. Ammianus Marcellinus later used the form "Lacus Brigantiae".