The Baths of Diocletian were the most magnificent public baths, or thermae, ever built in Rome. Erected between 298 and 306 AD, they covered more than thirteen acres and could accommodate up to 3,000 people at a time. They featured gyms, libraries, a pool of more than 3,500 square feet, and the quarters that formed the heart of every public bath: the frigidarium, the tepidarium, and the caldarium.
The frigidarium (that originates from the Latin word frigeo, which means "to be cold") was mainly used as a swimming pool, after using the hot-water baths or after exercising in the palaestra. The tepidarium, a word that means "to be hot" in Latin, was instead used for hot-water baths, for saunas or steam rooms. Finally, the tepidarium ("to be warm") was the warm bathroom of the Roman baths heated by a underfloor heating system. Its main feature was the pleasant feeling of radiant heat which directly enveloped the bodies from the walls and floor.
Michelangelo transformed these spacious rooms for the construction of Basilica of St. Mary of the Angels and the Martyrs. Other rooms of the Baths were replaced by the Convent of the Carthusians, designed by the artist himself.
The area occupied by the complex is now between the via del Viminale, Piazza della Repubblica, Via Torino, Via Cernaia, Via Volturno, Piazza dei Cinquecento, and Via XX Settembre.
The main entrance was located in the Via Volturno, while the other entrance had a huge exedra with steps and was perhaps used as a theater. This building was traced out in the realization of Republic Square, which is also known indeed as Piazza Esedra.
This private tour of Rome must include, in fact, Republic Square itself to see how the two twin buildings with porticoes that line the square echo the perimeter of the Baths.
Another visible sign of the Thermae is the church of San Bernardo alle Terme. The church was built in 1589 within a spheristerium of the Baths of Diocletian, which was a room for ball games. Similar to the Pantheon, St. Bernard also has a cylindrical shape with a dome and oculus. Statues of saints sculpted in the mannerist style can be found in a series of niches in the walls.
Finally, a must-see for this Rome tour is the National Roman Museum, which houses one of the most important archaeological collections in the world, featuring funerary inscriptions, statues, and reliefs and altars from the Baths themselves as well as from other parts of ancient Rome. Besides the exhibition, you can also enjoy, the sumptuous Aula Decima, where are exhibited the big tomb of the Platorini and two chamber tombs, decorated with frescoes and stuccoes, originally from the Necropolis of the Via Portuensis.
