Todi is a town and comune of the province of Perugia in central Italy. It is perched on a tall two-crested hill overlooking the east bank of the river Tiber, commanding distant views in every direction. It was founded in antiquity by the Umbri, at the border with Etruria; the gens Ulpia of Roman emperor Trajan came from Todi. In the 1990s, Richard S. Levine, a professor of Architecture at the University of Kentucky, included Todi in academic design exercises aimed at conceiving hypothetical improvements to the city and presented its results in a conference titled "The Sustainable City of the Past and the Sustainable City of the Future".