Tide mills: the route of one forgotten heritage

摘要

Tide mills are situated along the estuary of the River Tagus and are considered to be an important part of Portuguese heritage dating back to pre-industrialisation. These large solid structures made of stone have great architectural value and in former times were the basis of a small flour-milling industry which was particularly important in the making of 'biscoitos', a type of sea-biscuit used on ship voyages during the Portuguese Discovery period in the XV century. A significant number of these tide mills can be found in the River Tagus basin, close to the capital, Lisbon, however the largest number of tide mills is recorded in the Algarve region with a total of 47 units. This paper will establish the economic role tide mills played in Portuguese pre-industrial history. It will also outline the cultural aspects of tide mills, referring to their historical content, draw attention to their present state of abandonment, and in some cases ruin, and will highlight the urgent need for their classification, conservation and renovation.