The Persian Empire was one of the most mysterious civilizations in the ancient world. Persia became an empire under the Cyrus the Great, who created a policy of religious and cultural tolerance that became the hallmark of Persian rule. Engineering feats include an innovative system of water management; a cross-continent paved roadway stretching 1500 miles; a canal linking the Nile to the Red Sea; and the creation of one of the Seven Wonders of the World, the Mausoleum of Maussollos. The most advanced technologie and the biggest Empire of all time: P E R S I A (btw.. there where no 300 spartans against 10000..00? persians.. LOL al the empires of the west united for 1 reason: they're hatred of persia !) btw.. persia INVENTED reading and writing !