The Retiro, Madrid's principal park, showing the King Alphonso Monument in the distance.

The Retiro, Madrid's principal park, showing the King Alphonso Monument in the distance., H-197, Box: 3. Hispanic Society of America Postcard Collection, BENSON-MS Hispanic Society of America. Benson Latin American Collection, The University of Texas at Austin. https://archives.lib.utexas.edu/repositories/4/archival_objects/295949 Accessed September 26, 2026.