Not a single town, village, or city— not even The City of Enoch was exempt from annihilation. Every human settlement was utterly destroyed in the flood. At the time of the flood, The City of Enoch was likely the most ancient city in the world. This, of course, assumes that the city had not already been wiped off the map by the violence which plagued the pre-flood world (Genesis 6:11).
The city was built by none other than Cain himself, who named the city after his son Enoch (Genesis 4:17). And if the city did still exist at the time of the flood, it must have been one of the attractions of the pre-flood world. You can almost imagine someone crying out, "Come visit The City of Enoch! It was founded by a man who, according to legend, was a direct descendant of the first man!" If there were seven wonders of the (Incredibly) Ancient World, perhaps The City of Enoch topped the list.
It is, however, difficult to imagine that the citizens of the city would have embraced what they must have known to be true— that Cain was the son of a man who was directly created by the one true God. Perhaps they regarded the entire creation story as a myth. It was just a tale! A fictional tale passed down through many generations which had long ago lost its meaning. A fictional tale which no one even believed anymore, except for Noah. Perhaps the only story which they truly embraced was Cain's slaying of his brother. Such an event must have appeared heroic in the eyes of the wicked people of The City of Enoch (and all the other people living in the pre-flood world).
Although the people of The City of Enoch knew the truth, they suppressed it in unrighteousness. And what else would be expected? What else would be expected from a city which was founded upon the sweat of the first murderer? The City of Enoch was marching straight into judgment... and no one turned away from the march. No one turned to God in repentance.
The Destruction of The City of Enoch (Part 2) - Genesis 7:17-18
Zero More Years of Mercy (Part 1) - Genesis 7:16
The City of Enoch - Genesis 4:17-18
Noah's Timely Entry (Part 1) - Genesis 7:13-15
Cain and Abel: Two Routes - Genesis 4:1-2