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Border Monument No. 232, one of the boundary markers placed in the mid-1800s by the International Boundary Commission to demarcate the new international boundary lines after the Guadalupe Hidalgo Treaty of 1848 and the Gadsden Treaty of 1853. This monument is made of iron. Of the original 52 monuments only 7 were made of marble or iron; the rest were stone mounds built without mortar.
borderboundarymexicoobeliskmonumenttreatymarkermarbleUnited States