Calamity of Arna

]

The Calamity of Arna was a destructive geological event which took place in the western Arnic Sea from the morning of the 10th of Highfrost, 1 AC. The Peak of Winds, a supposedly dormant on the Arnic peninsula, and just 3 km west of Arna itself, erupted in one of the deadliest volcanic eruptions in recorded history. Simultaneously, a massive earthquake ripped through the island of Valentia as well as the Arnic and Achysian hinterlands, followed by a tsunami that swept across the Arnic and Valentian littorals. Arna, the cultural, political and economic center of the Arnic Empire, was leveled in the span of a couple hours, its population of one million people dying en masse to the superheated, falling ash, crumbling buildings, fires, and waves estimated to have reached a height of 40 meters.

The Calamity had a far-reaching impact in matters of scientific and theological understanding. The event was widely discussed and dwelt upon by contemporary and inspired major developments in  and. The foretelling of a "great calamity" by Vayon of Aratheda in the years preceding the event lent credit to the beliefs of his followers, kick-starting the religious reforms that would bring about the birth of modern Vayonism. The eruption caused a that lowered global temperatures for at least the following decade, bringing about crop failures which directly caused the Barbarian Exodus of the following century.

Nature of the event
Reconstructions of the eruption and earthquake and their effects vary considerably in the details but have the same overall features. The eruption lasted for two days. The morning of the first day saw early, smaller fissures and releases of ash and smoke on the mountain, though how much alarm this may have caused varies depending on the source.

Around 2:00 a.m. of the second day, the Peak of Winds violently erupted, spewing forth a deadly of super-heated  and  to an estimated height of 40 km and ejecting,  and  at 2 million tons per second. This was also the start of intense seismic activity throughout the entire eastern Arnic basin.

Arna, as well as several adjoining areas, was quickly obliterated and buried underneath massive s and. The soft, marshy ground of the city opened up in great fissures and sunk into itself. Sources place the receding of the sea just moments after, exposing coastal sandbanks littered with lost cargo and shipwrecks that crowds quickly flocked to. Half an hour later, a wall of water an estimated 40 meters tall swept through the sandbanks and coastal areas, penetrating over 1 km inward in some places.

Estimates place the earthquake's magnitude in the range of 9.0–10.0 and the volcanic eruption with a of 7.