Revelation says that Har-Megiddo is where the "kings of the earth" gathered before making war on Jerusalem. The original battle of Har-Megiddo occurred in the OT, when Josiah the righteous king died in battle against the Egyptians.
Anyway, the ancient seaport closest to Har-Megiddo is Caesarea (look at a map; Caesarea is almost due west), which is where Josephus says Titus marshalled his forces prior to marching on Jerusalem.
The text in Revelation says that “the kings of the whole world” would gather there. And while Rome was certainly big it was ruled by one ‘king’, Caesar. The Parthian Empire sat right along its eastern border.
The Romans and Parthians had battled over possession of the Levant during the time of Julius Caesar but that was shortly before the birth of Christ. Seems odd that the “kings of the whole world” in AD 70 would omit Rome’s major rival within walking distance of Jerusalem.