Archaeologists were surprised by the discovery of a Byzantine basilica in just six feet of water, 60 feet from the shore of Turkey’s Lake Iznik, near the ancient city of Nicaea. Locals knew there were ruins in the lake, but scholars were unaware of the 100-by-60-foot structure until Uludag University’s Mustafa Sahin recently spotted the clear footprint of the church in an aerial photo taken by the local municipality. Sahin thinks it’s likely the church was built in the late fourth or early fifth century, less than 100 years after Nicaea hosted the First Ecumenical Council in A.D. 325, convened by the emperor Constantine to establish key doctrines for the Eastern Roman Empire.