Eisenberg and Kowalewska (2025:144-145) noted that during the 363 CE Cyril Quake, "most buildings within and outside the city walls were completely or partly destroyed and not rebuilt." Segal et al. (2013: 160) suggest that the colonnades of the forum collapsed and Eisenberg and Osband (2022) report clear 363 CE destruction in multiple areas, including the Basilica, the Propylaeum and Theater of the Saddle Compound, and the Saddle Necropolis. In the Saddle Necropolis, Eisenberg and Kowalewska (2025:144-145) report that all structures were damaged and Eisenberg and Kowalewska (2024) describe damage to the foundations of funerary structures that they attribute to this same event — damage suggesting proximity to the epicentral region and high levels of local intensity. Eisenberg and Kowalewska (2025:144-145) report additional damage to the hypocausta of the Southern Bathhouse, and perhaps also to the odeion , the Roman temple in the Hellenistic Compound, and the porticoes of the colonnaded decumanus maximus.

The Basilica provides the clearest sequence of archaeoseismic evidence. Eisenberg (2021: 171–173) writes that the destruction of the building “was caused by the 363 CE earthquake,” supported by coins and pottery found immediately above the basilica floor and in the fill of Room III, the latest of which date to 361/2 CE. He notes that the recovered wall-painting and stucco fragments range from the first century BCE through the third century CE, with none assignable to the fourth century, indicating that the basilica had fallen into disuse before the quake. Eisenberg explains that there were “no broken marble statues or significant small finds” that would mark the sudden destruction of a functioning public structure, suggesting the building was already neglected prior to 363 CE.

Nonetheless, the earthquake produced fatal collapses: parts of the skeletons of at least four individuals were found beneath the fallen roof in the northern nave. Two relatively complete skeletons—an adult male and a young female—were discovered, the latter with “an iron nail, probably from the roof, embedded in her knee” and a dove-shaped gold pendant set with semi-precious stones lying at her neck. Eisenberg describes this pendant as “one of the most luxurious pieces of jewelry found to date in Hippos.” Following the disaster, the basilica was never rebuilt. Floors dated to the 380s CE were laid roughly one metre above the original pavement, covering the southern debris, while architectural fragments from the northern and central sections were looted and reused in nearby Byzantine constructions. During the Umayyad period, later buildings were erected atop the ruined basilica, some cutting through its southern walls and reusing its masonry.