Abhayagiri Monastery, located in Anuradhapura, is one of the most significant monastic complexes in Sri Lanka, reflecting the grandeur of the island's ancient Buddhist culture. It was established by King Valagamba in the 1st century BC and became a prominent center for Theravada Buddhism. Today, it's part of the UNESCO-listed Anuradhapura World Heritage Site. Abhayagiri is renowned for its spectacular stupa, which once stood approximately 100 meters high, making it one of the greatest architectural feats of its time. The monastery is spread over 200 hectares, encompassing a rich collection of archaeological and architectural wonders including moonstones, guard stones, and a sophisticated network of reservoirs and waterways. It was not just a religious center but also a place of learning, attracting scholars from across Asia. The remains of various structures at the site reveal influences from various periods and cultures, reflecting the political, religious, and social changes in Anuradhapura.