Fortress of Humaitá
Coordinates: 27°04′S 58°31′W / 27.067°S 58.517°W
The Fortress of Humaitá (1854–68), known metaphorically as the Gibraltar of South America, was a military installation near the mouth of the River Paraguay. A strategic site without equal in the region, it was "the key to Paraguay and the upper rivers". It played a crucial role in the bloodiest conflict in the continent's history: the Paraguayan War.
The site was a sharp horseshoe bend in the river; practically all vessels wishing to enter the Republic of Paraguay – and indeed to sail to the Brazilian province of Mato Grosso – were forced to navigate it. The bend was commanded by a 6,000-foot (1.8 km) line of artillery batteries, at the end of which was a chain boom which, when raised, detained the shipping under the guns. The fortress was protected from attack on its landward side by impassible swamp or earthworks which, at their greatest extension, comprised a system of trenches stretching for 8 lineal miles (13 km), had a garrison of 18,000 men and deployed 120 cannon. At its zenith Humaitá was reputed to be impassable to enemy shipping.
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