Complex sentence: Clifford's Fort, located on the Fish Quay, was built in the 17th century (1672) as a coastal defence against the Dutch, and also played a role during the Napoleonic Wars.
Split into simpler sentences: Clifford's Fort, located on the Fish Quay was built in the 17th century (1672) as a coastal defence against the Dutch. The Fort also played a role during the Napoleonic Wars.