Niebla Castle is a medieval fortress in Huelva province constructed during the latter half of the 15th century by the 2nd Duke of Medina Sidonia. The castle features a rectangular floor plan with eight towers of varying shapes and two main enclosures surrounding a columned courtyard. Built atop the remnants of an earlier alcázar demolished in 1402, it represents the military sophistication of late medieval Andalusia. The fortress endured a brief siege by Blake and Zayas's division in 1811 during the Peninsular War. Today visitors can explore its dungeons, ramparts, and exhibits with informative displays in multiple languages, providing insights into its strategic importance.