Archeological investigation has shown that the reverence of the Grotto of the Annunciation dates back to the third century, when Jewish Christians erected a first modest church replicated on the synagogues of the day. The second church, a small edifice with a spherical apse and a foyer at the west end, was constructed in the fourth century for the Empress Helen, Constantine the Great's mother, by a converted Jew called Joseph of Tiberias. The third church was constructed in the early 12th century by Tancred, Prince of Galilee, and was on a noticeably larger scale than its predecessors. It was a three-aisled church 246 feet long by 98 feet wide.