Another source states that Isabella built the weir ten years earlier incorporating a huge gap in the centre through which boats could pass. This gap however, was eventually blocked between the years 1307 and 1377 by her kinsmen Hugh Courtenay and his son also named Hugh, and as mentioned it had the effect of preventing ships reaching the quay at Exeter and thus forcing them to use the nearby port of Topsham. The ship owners had to pay a fee the Courtenay's for the privilege.
From the 16th through to the 18th century the city played an important part in processing and exporting woollen cloth.