El Retiro Park began as a royal retreat, its name the Spanish word for withdrawal. Philip IV built a pleasure palace here in the 1630s, with a boating lake where miniature galleons fired dummy cannons for the court's amusement. Almost nothing survives; Napoleon's troops used the trees for target practice. One did make it: an Ahuehuete nearly 400 years old, spared only because soldiers could balance a cannon between its branches.

The park opened to the public in 1868, the year the lake froze and citizens skated on it to celebrate the fall of Queen Isabel II. Today rowboats replace the galleons, and the only devil in sight is a bronze fallen angel whose base sits at precisely 666 metres above sea level.

VoiceMap's self-guided audio tours trace Retiro's arc from royal excess to public life, connecting the park's surviving fragments to the dynasties and disasters that shaped them.