The Kingdom of Polonnaruwa was a significant medieval kingdom in Sri Lanka, flourishing from the 11th to the 13th centuries. It became the capital after the fall of the Anuradhapura Kingdom and is known for its impressive architectural achievements, including temples, palaces, and gardens. The kingdom is famous for the Gal Vihara, a rock temple featuring stunning Buddha statues, and the Royal Palace, which showcases the advanced engineering of the time. Polonnaruwa was a center of trade, culture, and agriculture, contributing to the rich history of Sri Lanka.