There is evidence that the beginning of the human study of medicine was around 3500 B.C.E. Religious priests and medicine men were the first medical practitioners. In ancient Mesopotamia, c. 3500 B.C.E., there were two kinds of medicine men–the "ashipu" who diagnosed the disease or injury, and the "asu" who practiced healing medicine and was practiced in herbal remedies. Practices in this early period included bandaging and making plasters for wounds. Although many patients were treated in their home, the first houses of medicine were often placed near rivers, so the evil substances and spirits would be washed away. This tradition continues into the Greek and Roman periods, both societies placing their centers of healing near the ocean, a river or spring. Temples to gods and goddesses of healing were often used as healing centers, with spiritual and scientific remedies practiced there.