Complex sentence: On the quay there is a machicolated clock-tower which is a survival of the defensive walls of the 14th century; and the town-house, containing a small museum and a library, is a quaint relic of the 16th century.
Split into simpler sentences: On the quay there is a machicolated clock-tower which is a survival of the defensive walls of the 14th century. The town-house, containing a small museum and a library, is a quaint relic of the 16th century.