In the foundation charter of Tihany, the founder King Andrew I also made a provision about the final resting place of himself and his family when he designated it within the walls of the monastery of St. Aignan. According to the chronicles, the monarch's will was fulfilled, and Andrew, who was wounded in a battle with his brother, Béla I, at the gates of Moson and died in the royal manor house in Zirc, was laid to rest in the monastery of Tihany in December 1060. In a similar way, there is historical evidence that his younger son, Prince David, was buried in the monastery founded by his father. The burial place of Queen Anastasia of the Grand Duchy of Kiev remains unknown to this day, although it is possible that her remains were eventually buried in the King’s Crypt.

With the help of radiocarbon dating of human remains collected over the centuries from the King’s Crypt and reinterred in 3 wooden caskets following the most recent excavation in 1953, bones from the early 11th-12th century burial period could be clearly separated. Parallel investigations in several laboratories (Mannheim, Poznan, Debrecen) showed that the older remains, which were almost undoubtedly part of the royal burials, were the bones of one or two adult males. Among these bones we can look for the remains of King Andrew I and his son Prince David. The poor state and the fragmentary nature of the bones did not allow for a detailed anthropological and palaeopathological study. Thus, the presumed Humanist history writers from Hungary tradition of King Andrew I suffering from gout was not confirmed by the tests.

However, the poor overall condition of the bones did not only make morphological research difficult. According to archaeogenomic studies, the remains associated with the royal family belong to the so-called R1a male archetype, which is very common in Eastern Europe, and to which the genetic type obtained from the bone remains of Béla III belongs. However, a more precise identification and authentication with the known subgroup of the paternal lineage of the Árpád dynasty was not possible due to the extensive damage and dilution of the genetic material extracted from the centuries-old bones from the King’s Crypt.

The scarcity of bone remains from the 11th and 12th centuries, in addition to the hardships of the past thousand years, also shows that for a long time, the only ones buried in the crypt were Andrew I and his immediate family. In these early centuries, the Benedictine monks of Tihany did not allow their founder's peace to be disturbed by other burials. This is evidenced by the fact that Andrew II supported the Benedictines of the monastery of St Aignan with further royal donations to care for the tomb and memory of his great ancestor and his family. The quantity of early burials limited to the royal family has been confirmed by archaeological research.

Most of the bone remains are from burials dating from the 15th century onwards. The remains of mainly adult males are those of soldiers of the Ottoman wars, or of representative members of the monastic life that began again at the end of the 17th century, or even of abbots.