A nymphaeum dedicated to a local water nymph, Coventina, was built along Hadrian's Wall, in the northernmost reach of the Roman Empire.Such nymphaea existed in Corinth, Antioch and Constantinople; the remains of some twenty have been found in Rome and many in Africa.Initially they were often decorated with geometrical mosaics often incorporating shells, but by the end of the century could contain ambitious figure subjects.[5] The term nymphaeum was also applied to the fountains of water in the atrium of the Christian basilica, which according to Eusebius were symbols of purification.A nymphaeum for al fresco summer dining featuring artificial grottoes with waterflows was designed by Bartolomeo Ammanati (1550–1553), and was reintroduced at the Villa Giulia, Rome.