Mount Gerizim
In the Classical period, probably in the 5th or 4th century BCE, the Samaritans built a temple at the summit of the mountain. This became a focal point for their sect analogous to that played by Jerusalem in Judaism. The temple was surrounded by fortifications (comp. II Macc. v. 23), which survived the destruction of the temple itself (Josephus, "Ant." xiv. 6, § 2; xviii. 4, § 1; "B. J." iii. 7, § 32). The Temple was destroyed by the Hasmonean king John Hyrcanus in the second century BCE but continues to be the center of Samaritan religion to this day.
When Christianity became the dominant religion in the Roman Empire, Samaritans were barred from worshipping on Mount Gerizim. A church was built on its summit and a wall constructed to defend the church from Samaritan raiders. This was one of the main causes of the Samaritan revolution under Julianus ben Sabar.