As you walk around the Parco del Colle Oppio, you will notice a number of ruins - these belonged to Trajan's baths.
This extraordinary bath complex was built on the remains of Nero's Golden House which in turn, provided their foundation. These baths were designed by Trajan's architect, Apollodorus, and would later become the model for all the great imperial baths.
The complex covered a surface of almost 10,000 square meters and comprised gymnasiums, saunas, hot, cold, and tepid baths, a large swimming pool, massage rooms, libraries, gardens and areas for meeting and conversing.
Roman baths originally provided citizens a place to wash in; they soon became a place for socializing for a population that enjoyed 180 holidays a year. Admission was either free or it cost next to nothing, guaranteeing access to all social classes. People whiled away entire afternoons in one of the 800 Roman baths.