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The records of the U.S. Embassy in Madrid are part of RG 84: Records of the Foreign Service Posts of the Department of State. These records are available on-site at the National Archives in College Park, MD. The available finding aids for these records are mainly available online, but much will depend on the time period you seek. We suggest you begin your research with an advanced search in the National Archives Catalog. The link provided is for series-level results in RG 84 relating to Madrid. For many of the series, you will find file units or container list in the Catalog.
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