Douro river sightseeing and river tour boat 'Borda d'Água', registration P-86-AL, during a cruise near Oporto.

'Borda d'Água' is one of the many similar, modern vessels used by tourists to discover Oporto from the river. It is a replica of the traditional Douro river boats, called 'rabelo', usually of 19 to 23 m in length and 4.5 m width. The 'rabelo' boats had a flat bottom (no keel). These traditional boats were used to carry wooden barrels of Port Wine to the wine warehouses located at Vila Nova de Gaia (left bank of the Douro river) from the vineyards upstream, for aging, and subsequently for export.