Castillo de la Estrella is one of Spain's largest medieval archaeological sites, located in Montiel, Ciudad Real, atop a steep hill at 961 meters elevation. Originally constructed by Arabs in the 9th century as Munt-Yil, it resisted as a Muslim stronghold until 1228, following a two-year Christian siege. The fortress encompasses a monumental complex including the castle ruins, remnants of the medieval town that occupied its slopes until the 15th century, the Vicaría of Montiel, and the battlefield of a 1369 confrontation involving King Pedro I of Castile. Reformed during the 18th century, the castle became municipal property in 2012 and is now managed by the Castillo de La Estrella Foundation, serving as a significant cultural and historical landmark for the region.