Baths of Constantine

Baths of Constantine was a public bathing complex built on Rome's Quirinal Hill, beside the Tiber River, by Constantine I, probably before 315.
The last of Rome's bath complexes, they were constructed in the irregular space enclosed by the vicus Longus, the Alta Semita, the clivus Salutis and the vicus laci Fundani. And as this was on a side-hill, it was necessary to demolish the 4th-century houses then on the site and make an artificial level over their ruins. Because of these peculiar conditions, these thermae differed in plan from all others in the city – no anterooms were provided on either side of the caldarium, for instance, since the building was too narrow. The building was oriented north-south so as to heat it using the sun, with principal entrances on the west side, where there was a flight of steps down from the hill's summit to the Campus Martius, and on the middle of the north side.

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