Zechariah 12 v 10
"And they (Jerusalem) shall look upon ME whom they pierced (whilst inside of the son of Mary body) and they (the Jews) shall MOURN for HIM (Jesus) as one mourneth for his only son, and shall be in bitterness for him, as one that is in bitterness for HIS [own] firstborn."
12:11 In that Day shall there be a great mourning in Jerusalem, as the mourning of Hadadrimmon in the Valley of Megiddon (as they too are EXECUTED).
The Valley of Megiddon is below the mountains of Megiddo - Har-Megiddo or in English - Armageddon - ARMAGEDDON. Christ's Second-Coming