Complex sentence: The first excavation in 1968, conducted on the terrace at the base of the cliff, unearthed two arrowheads: one probably dating to the late Stone Age, and one to the Early Metal Period.
Split into simpler sentences: The first excavation was conducted in 1968 on the terrace at the base of the cliff. Two arrowheads were unearthed: one probably dating to the late Stone Age, and one to the Early Metal Period.