Marktbreit am Main is a town in Kitzingen in the Regierungsbezirk Unterfranken in Bavaria, Germany. It is at the most southern point of the Main river. Marktbreit is the birthplace of Alois Alzheimer who first identified the symptoms of what is now known as Alzheimer's disease. With its suburb Gnodstadt, Marktbreit has about 3,700 residents.