The carreira da Índia and the problem of the access to the Tagus river rill

navigation obstacles during the sixteenth and seventeenth centuries

Abstract

In late 16^th century, due to fortification works, the navigation channels of the Tagus river rill began to silt, to narrow and to present a smaller depth, strongly affecting the shipping, especially carreira da India's ships, themselves characterized by its large dimensions. The largest concern was the carreira de São Gião (São Julião), the northern navigation channel, and the most important one for vessels on their way to Lisbon, which became more susceptible of being the stage of beaching and shipwrecks. This study aims to contribute to the discussion of these subjects, while attempting, at the same time, to understand when the carreira de Alcáçova, in the South Channel, started being used by Navigation to enter the Tagus river, and under which conditions.