What is the smallest city in your country that everyone can still instantly recognise the name of? What is it famous for?
In the United States, I'd probably name Oregon City, the famous end of the Oregon Trail and the first city founded west of the Rocky Mountains during the pioneer era. Its population is only 37,000.
Unfortunately, I would guess that school shooter locations are probably the most easily recognised in the US. Uvalde has a population of ~15,000, for instance.