These monuments were originally natural grottoes, which tradition assigned as habitations to the local nymphs. They were sometimes so arranged as to furnish a supply of water, as at Pamphylian Side. A nymphaeum dedicated to a local water nymph, Coventina, was built along Hadrian's Wall, in the northernmost reach of the Roman Empire. Subsequently, artificial grottoes took the place of natural ones.
Jerash, the Gerasa of Antiquity, is the capital and largest city of Jerash Governorate (محافظة جرش), which is situated in the north of Jordan, 48 kilometres (30 mi) north of the capital Amman towards Syria. Jerash Governorate's geographical features vary from cold mountains to fertile valleys from 250 to 300 metres (820 to 980 ft) above sea level, suitable for growing a wide variety of crops.
A strong earthquake in 749 AD destroyed large parts of Jerash, while subsequent earthquakes along with the wars and turmoil contributed to additional destruction. Its destruction and ruins remained buried in the soil for hundreds of years until they were discovered by German Orientalist Ulrich Jasper Seetzen in 1806 to begin excavation and to return life to rise to the current Jerash by inhabitants of old villages. Then followed 70 years after by the community of Muslims, Circassians, who emigrated to Jordan from the Caucasus in 1878 after the Ottoman-Russian war. And a large community of people of Syria at the beginning of the 20th century.