Qal'at al-Bahrain is a historical fort located on the island of Bahrain. It dates back to the 16th century and was built by the Portuguese as a strategic military outpost. The site showcases a blend of various architectural styles, reflecting the influences of different cultures over the centuries. The fort is part of a larger archaeological site that includes ancient burial mounds and remnants of a Dilmun civilization. In 2005, Qal'at al-Bahrain was designated a UNESCO World Heritage Site, recognizing its significance in understanding the region's history and cultural heritage.