Marine archaeologists have successfully mapped a lost maritime trade route dubbed the 'Tin and Alum' Seaway, which connected the mining districts of Cornwall directly to the industrial centers of the Ottoman Empire in the 15th century. Using deep-sea autonomous vehicles, the team identified a series of shipwreck clusters along the Atlantic coast of Portugal that carried refined tin ingots and Mediterranean alum.
The findings, published in the Journal of Maritime Archaeology, suggest a much higher volume of direct trade between Northern Europe and the Levant than previously documented. This research reveals how the demand for dye-fixing alum in English textile production and Ottoman bronze casting fueled a specialized maritime corridor that bypassed traditional overland routes.