Darius the Great's Best Friend

Darius visited Babylon, did the things, went to the temple and grasped the hands of the Belmarduk statue. The whole time worried about how the hell he was going to pay for all this. When the harem finally departed from the city off to its next location, the new high priest tried to be his new best friend. Now he was giving the great king an unsolicited tour of Babylon on his way out. As they passed through the gate, the priest pointed above them and said, that spot with the inscriptions is the tomb of Queen Nittokris. He glanced up. Why'd she put her tomb over the gate? That's weird. You don't