The Cairo Citadel, also known as the Citadel of Saladin, is a historic fortress perched atop the Mokattam Hills, offering panoramic views of Cairo. Commissioned by Salah ad-Din (Saladin) in 1176 CE, it was constructed to fortify the city against Crusader attacks and served as Egypt's seat of government for nearly 700 years, until the 19th century. Over the centuries, the Citadel was expanded by successive rulers, including the Mamluks and Muhammad Ali Pasha, who added significant structures that define its current form.

One of the most prominent landmarks within the Citadel is the Mosque of Muhammad Ali, also known as the "Alabaster Mosque." Commissioned by Muhammad Ali Pasha in 1830 and completed in 1857, the mosque was built in memory of his son, Tusun Pasha. Its design was inspired by the Ottoman architecture of the Sultan Ahmed Mosque in Istanbul, featuring a large central dome flanked by semi-domes, twin minarets reaching 84 meters, and extensive use of alabaster for its interior and exterior walls.

The mosque's interior is adorned with intricate decorations and houses the tomb of Muhammad Ali Pasha himself. Notably, the mosque's courtyard contains a clock tower gifted by King Louis Philippe of France in exchange for the obelisk that now stands in Paris's Place de la Concorde. ​

Today, the Citadel complex includes several museums, such as the Egyptian Military Museum, the Al-Gawhara Palace Museum, and the Police Museum, each offering insights into Egypt's rich history. The Citadel is a UNESCO World Heritage Site and remains a testament to Cairo's historical and architectural legacy.