In the late 18th century, Japan was subjected to significant volcanic activity, particularly on the island of Kyūshū. Mount Unzen, an active composite volcano, had been erupting off and on, with residents living in its shadow acutely aware of the risks posed by such powerful geological forces. On the fateful day of May 21, 1792, a critical event took place: the unstable lava dome on the mountain's summit collapsed. This catastrophic failure of the dome was exacerbated by the ongoing volcanic activity of Mount Unzen, creating conditions ripe for disaster. As the dome gave way, it sent a massive torrent of volcanic debris rushing down the sides of the mountain and into the surrounding waters, displacing vast amounts of water and resulting in a deadly tsunami that struck the nearby towns and villages.The tsunami devastated the coastal settlements, resulting in nearly 15,000 fatalities, and caused widespread destruction of homes, infrastructure, and livelihoods. Notably, the geographic configuration of the region, including surrounding valleys and the proximity of the ocean, amplified the tsunami's impact. The event highlighted the vulnerabilities of coastal communities to volcanic tsunamis and forced a reassessment of disaster preparedness in Japan. Survivors faced overwhelming challenges in the aftermath, including the need for rebuilding and recovery amidst the loss of so many lives.Furthermore, this incident underscored the interaction between geological disasters and human geography, drawing attention to the inherent risks in living close to active volcanic regions. It also prompted a greater understanding of the dynamics of volcanic activity and tsunamis, factors that would contribute to the development of both scientific inquiry and disaster response structures in Japan and beyond.