Cultures > Greco-Roman Egypt
See Ptolemaic Kingdom.
Alexander never got to see Alexandria finished as he was never able to return to Egypt like he planned. The city was meant to be the grandest in all the Mediterranean. It was going to be the capital for his new Mediterranean empire and basically be a super Tyre or Carthage that would have probably been one of the most grand cities in the entirety of history if Alexander did not suddenly die.
The fragmentation of Alexander's empire left it prime for invasions from the Roman Empire and after defeating the Punics and Carthage the Romans set their sights on the Egyptians.