The survey of churches of the Byzantine and Crusader periods in Israel has noted several hundred foundations, commemorating the loca sancta. Many of these ruins were discovered and studied in recent years and are presented here for the first time. The first section comprises introductory material on ecclesiastical architecture from the Byzantine to the Crusader periods, as well as ancient Christian liturgy. Articles in other sections present a wide spectrum of Christian archaeology: liturgy, tradition, history, architecture, art and epigraphy.