Abhayagiri Dagoba is a Buddhist stupa located in Anuradhapura, Sri Lanka. The stupa was built during the reign of King Valagamba in the first century BCE. It was the second tallest stupa in Sri Lanka, standing at a height of 115 meters. The name Abhayagiri means "fearless hill" in Sinhalese.

The stupa is believed to contain a sacred relic of the Buddha - a tooth of the Buddha. It is one of the most important pilgrimage sites for Buddhists in Sri Lanka. The stupa has been rebuilt several times over the years, most recently in the 20th century. The current stupa is about 75 meters tall and is surrounded by a large complex of buildings, including a monastery, a library, and several other structures.

The Abhayagiri Dagoba was a major center of Buddhist learning and culture during the Anuradhapura period. It was the site of a large monastic complex that housed thousands of monks. Many important Buddhist texts were written and studied here, and the complex was known for its large collection of books and manuscripts.

Today, the Abhayagiri Dagoba is a popular tourist attraction and pilgrimage site. Visitors can explore the complex and view the stupa and other structures. The site is also known for its beautiful carvings and sculptures, which are considered some of the finest examples of Sri Lankan Buddhist art.