Todi is perched on a tall two-crested hill overlooking the east bank of the river Tiber, commanding distant views in every direction. According to the legend, said to have been recorded around 1330 BC by a mythological Quirinus Colonus, Todi was built by Hercules, who here killed Cacus, and gave the city the name of Eclis.
Historical Todi was founded by the ancient Italic people of the Umbri, in the 8th-7th century BC, with the name of Tutere. The name means "border", being the city located on the frontier with the Etruscan dominions. It probably was still under the latter's influence when it was conquered by the Romans in 217 BC. According to Silius Italicus, it had a double line of walls that stopped Hannibal himself after his victory at the Trasimeno. In most Latin texts, the name of the town took the form Tuder.