Fortress of the Immaculate Conception built
1673 CE.
Shown on the map at 11.019°, -84.397°.
The Fortress of the Immaculate Conception, (Spanish: El Castillo de la Inmaculada Concepción) is a fortification located on the southern bank of the San Juan River (Río San Juan), in the village of El Castillo in southern Nicaragua. The fortress is situated approximately 6 kilometers from the border with Costa Rica, at the Raudal del Diablo rapids of the San Juan River. It was completed in 1675 as part of a series of fortifications along the San Juan River, to defend against pirate attacks upon the city of Granada (which can be reached by navigating upstream from the Caribbean Sea along the San Juan River into Lake Nicaragua). The settlement of El Castillo and its fortress continued to be strategically important to the Captaincy General of Guatemala until the late 18th century. An important historic landmark of Nicaragua, the fortress is on a list of sites as an initial stage in achieving World Heritage Site status with the United Nations Educational, Scientific and Cultural Organization (UNESCO).
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