The General Archive of Simancas.
General view of the Archive of Simancas in 1858.
The General Archive of Simancas is an archival project conceived by Philip II in 1580. The project was designed and constructed by royal architect Juan de Herrera and was the first custom-built archive. It preserves coherent documentation created by the political and administrative structures of the Spanish Monarchy until the 19th century; including the Habsburg Councils, the Bourbon Secretariats, and the Treasury department. The Archive holds important information on European and global territorial history from the 16th-19th centuries.