The Naiads (Naiades) were nymphs of bodies of fresh water and were one of the three main classes of water nymphs - the others being the Nereids (nymphs of the Mediterranean Sea) and the Oceanids (nymphs of the oceans). The Naiads presided over rivers, streams, brooks, springs, fountains, lakes, ponds, wells, and marshes.
The Naiad was intimately connected to her body of water and her very existence seems to have depended on it. If a stream dried up, its Naiad expired. The waters over which Naiads presided were thought to be endowed with inspirational, medicinal, or prophetic powers. Whoever drank of these magical waters would be inspired, thus the Naiads were themselves considered prophetic and were frequently worshipped by the ancient Greeks in association with divinities of fertility and growth. Hence all persons in a state of rupture, such as madmen, poets, seers and prophets, were said to be caught by the Nymphs.