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A recent historical discovery has confirmed the exact quarry that provided the limestone used to build the Alamo.
Alamo officials said excavation for the San Antonio Zoo's new gorilla habitat revealed large amounts of unearthed limestone.

Geological testing and historic research confirmed that this site was the primary source of stone used in the 1700s to build the Alamo Church. It was also used for other structures.
Thursday, March 6, marks the 189th anniversary of the Battle of the Alamo.
In a statement, officials explained that "excavation for San Antonio Zoo’s new gorilla habitat Congo Falls and The Ralston (event center), large amounts of limestone were unearthed, prompting further investigation. Through extensive geological testing and historical research conducted by Highbridge Materials Consulting, Inc., experts have now verified that the quarry — located on the far west side of the Zoo — was a primary source of stone used in the 1700s to build the Alamo Church and other historic structures in San Antonio."
The statement added: "Originally established in 1718, Mission San Antonio de Valero, later known as the Alamo, was relocated to its current site in 1724. It was constructed using locally sourced limestone. Confirming this quarry’s location provides an unprecedented link to the materials that shaped San Antonio’s historic built environment."
The discovery came as the Alamo and the area around it undergoes a $550 million redevelopment project, which is scheduled to be completed in 2027.
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