Complex sentence: Exeter Cathedral and Christchurch Priory, also constructed during the 14th Century are built of Portland stone, its superb characteristics has ensured a popularity amongst masons and architects, that has endured ever since.
Split into simpler sentences: Exeter Cathedral and Christchurch Priory, also constructed during the 14th Century are built of Portland stone. Its superb characteristics have ensured a popularity amongst masons and architects that has endured ever since.