Which Byzantine basilica in Ephesus was built under Emperor Justinian I over the supposed tomb of Saint John?

The Basilica of Saint John in Ephesus was built under Emperor Justinian I over the supposed tomb of Saint John.

The basilica was erected in the sixth century at Ephesus, in present-day Turkey. Justinian sponsored the construction as part of the imperial building program that transformed important Christian and pilgrimage sites across the Byzantine Empire.

Its plan was a large cruciform basilica with several domed bays. The church was built around a pre-existing memorial associated with John the Apostle, whose Gospel tradition made Ephesus a significant Christian center. Pilgrims visited the site because of its connection with the apostle.

The basilica is now a substantial archaeological ruin near Selçuk. It should not be confused with the much earlier Church of Mary in Ephesus or with the Basilica of Saint John in other cities.