Ratu Boko is located approximately 3 kilometres south of Prambanan Temple, situated on a hilltop at about 195.97 metres above sea level. Unlike typical ancient temples, Ratu Boko is actually the remains of a palace complex. For this reason, it is often referred to as Kraton Ratu Boko. According to local legend, this site was once the palace of Ratu Boko, the father of Lara Jonggrang.

The Ratu Boko complex is believed to have been established in the 8th century by the Buddhist Syailendra Dynasty, and later taken over by the Hindu rulers of Mataram. This transition of power resulted in architectural and cultural elements influenced by both Buddhism and Hinduism.

One of the most important findings at the site is the Abhayagiriwihara Inscription, dated to 792 AD. Written in pranagari script—a hallmark of Buddhist inscriptions—it states that King Tejapurnama Panangkarana, believed to be Rakai Panangkaran, ordered the construction of Abhayagiriwihara. His name also appears in several other historical inscriptions, including the Kalasan Inscription (779 AD), Mantyasih Inscription (907 AD), and Wanua Tengah III Inscription (908 AD).

The term abhaya means “peace,” and giri means “hill,” so Abhayagiriwihara translates to “a monastery built on a peaceful hill.” During the reign of Rakai Walaing Pu Kombayoni (898–908 AD), the monastery was renamed Kraton Walaing.

Today, the Ratu Boko site spans a vast area and features several building groups. Although many structures now lie in ruins, the site remains a significant historical landmark with a rich blend of cultural and architectural heritage.