Complex sentence: At both bridgeheads stone churches with gate passages were erected, at the western end St. Benedicti and at the eastern end St. Aegidien, which was previously there as a existed a bridge chapel (first mentioned in 1110).
Split into simpler sentences: At both bridgeheads stone churches with gated entrance-ways were erected; at the western end St. Benedicti and at the eastern end St. Aegidien. St Aegidien was previously a bridge chapel (first mentioned in 1110).