This is close to both Ephesus and the Temple to Artemis but is the focus of Christian mysteries. The seven sleepers are 7 Christian men who were said to have been walled up in a natural grotto to save them from persecution.
Safe in their cave they fell asleep only to wake 200 years later around 435CE. Walking down into Ephesus they were amazed by the number of churches and the ability for them to worship safely. Eventually they died natural deaths and were buried in the cave where they had slept.
Obviously the site of such a miracle became a place of pilgrimage and a church and mausoleum added later.
Many others also wanted to be buried on such a sacred site ( may be in hope of waking up themselves in the future) and there are many other grave slots above the original grotto. This was a major place of pilgrimage up to the 15CE but nowadays it doesn't seem much visited. There were just a handful of other visitors despite the location of a busy tourist trap just below on the road.
These legends of people falling asleep only to wake and find that many years have passed are found worldwide. Indeed King Arthur is said to slumber under Britain awaiting the time when he will waken and save the country in its time of need.
Possibly the most interesting thing about this site was the discovery of a series of clay lamps found in the grotto. Many were decorated with Christian themes but many other bore pagan images such as the head of the Attis ( Consort of Cybele and a god of death and resurrection, born of a virgin mother....sound familiar?).
