pissposting

Yes, it's a town. Auschwitz is German for Oświęcim, which is a town where the barracks were repurposed for the death camp. They then built a second one, Auschwitz - Birkenau, 3km from Brzezinka (Birkenau). That one was purpose built instead of repurposed.

Nearly if not every concentration camp and death camp was named after a town or city it was built in. These weren’t hidden off in forests somewhere, they were built in locations with people able to staff and support them. This is part of how we know there’s no way any reasonably informed citizens didn’t know the holocaust was happening.