Viage al Estrecho de Magallanes Por el Capitan Pedro Sarmiento de Gamboa En los anos de 1579. y 1580.

Pedro Sarmiento de Gamboa, a Spanish navigator, cosmographer, and historian, undertook an exploratory survey of the Straits of Magellan in 1579–1580 under orders from Viceroy Francisco de Toledo. The expedition was part of Spain’s response to the increasing presence of English privateers in South American waters, particularly Francis Drake’s circumnavigation, which had revealed the vulnerability of Spanish Pacific possessions. Sarmiento was tasked with charting the strait, assessing its navigability, and identifying potential sites for fortifications to secure Spanish control over the crucial passage between the Atlantic and Pacific. Over the course of his voyage, he produced one of the earliest systematic surveys of the strait, recording hydrographic details, anchorages, and the conditions of wind and tide. His observations not only informed Spanish imperial strategy but also contributed to European geographical knowledge of the southern continent. Although the subsequent Spanish attempt to colonize and fortify the strait (1581–1587) ended in failure, Sarmiento’s survey remains a significant episode in the history of early modern exploration, illustrating the intersection of navigation, empire, and maritime defense.