The Citadel of Qaitbay is a 15th-century defensive fortress located on the Mediterranean coast of Alexandria, Egypt. It was built by the Mamluk Sultanate to protect the city from the threat of Ottoman invasion. The citadel was constructed on the ruins of the ancient Lighthouse of Alexandria, which was one of the Seven Wonders of the Ancient World.

The citadel consists of a large central courtyard, surrounded by fortified walls and towers. It was designed to withstand cannon fire and other types of attacks, and has a series of traps and obstacles that would make it difficult for an enemy to penetrate. Inside the citadel, there is a mosque, which was also built during the Mamluk period. The mosque features beautiful stonework, carved wooden doors, and a large dome.

Today, the Citadel of Qaitbay is a popular tourist attraction, with visitors coming from all over the world to see this impressive piece of history. From the top of the citadel, visitors can enjoy panoramic views of the Mediterranean Sea and the city of Alexandria. The citadel also houses a small naval museum, which displays weapons, armor, and other artifacts from the time of the Mamluks and Ottomans.