There is no known time in history when hailstones this large fell on the earth. In keeping with the symbolism of the book of Revelation, we need to understand these hailstones as describing God's finding ways to destroy what Satan (Ephesians 2:2) has prompted mankind to build. In his own heavenly, almighty way, the Lord God wrecks the Babels man builds under the instigation of the devil. So his kingdom, motivated by the fury of Revelation 12:17 and empowered by beasts as those of Revelation 13:1–18, cannot succeed.
21 And great hailstones, about one hundred pounds each, fell from heaven on people; and they cursed God for the plague of the hail, because the plague was so severe.