> Roman Egypt preserves a much larger slice of our evidence than any other place in the ancient world. This comes down to climate (as do most things); Egypt is a climatically extreme place. On the one hand, most of the country is desert and here I mean hard desert, with absolutely minuscule amounts of precipitation. On the other hand, the Nile River creates a fertile, at points almost lush, band cutting through the country running to the coast. The change between these two environments is extremely stark [...]

> That in turn matters because while Egypt was hardly the only arid region Rome controlled, it was the only place you were likely to find very many large settlements and lots of people living in such close proximity to such extremely arid environments (other large North African settlements tend to be coastal). And that in turn matters for preservation.

https://acoup.blog/2022/12/02/collections-why-roman-egypt-wa...