To the untrained eye, these ruins look unprepossessing to say the least, but archaeologists maintain that the remains of this ancient mud-brick complex represent the oldest purpose-built church in the world. The foundations date back to the late 3rd or early 4th century, and the church was probably in use for about a century before an earthquake devastated the region. Layers of sand have helped preserve the walls, some of which are more than two meters high.