Sodom and Gomorrah were destroyed because of vile affections, and breaking God's laws.
Jude 1:7. "Even as Sodom and Gomorrah, and the cities about them in like manner, giving themselves over to fornication, and going after strange flesh, different flesh, are set forth an example, suffering vengeance of eternal fire." There were many reasons God destroyed Sodom and Gomorrah, homosexuality and strange practices were just a few of reasons. They were also corrupt, and evil. Strange flesh is flesh that is different than what is rightfully ours to claim for our spouses body. Flesh that is forbidden by God for us to have. It is flesh outside the bounds of God's laws; hence the term sexual deviance, to deviate from what is acceptable to God.
Genesis 19:24. "Then Hashem rained brimstone and fire on Sodom and Gomorrah, from Hashem out of the heavens. So He overthrew the cities, all the plain, all the inhabitants of the cities, and what grew on the ground.
No where else on earth is the sulphuric content found to be 98% pure sulfur, with measurable amounts of magnesium. Researchers found that other places in the world have 40% sulphur, but not the high content of the cities of the plain.
The blast was fire and brimstone. Amazingly, there are no other ancient ruined cities anywhere else on the planet covered with pure sulphuric balls with its ruins turned to ash. When limestone turns to ash there must be very intense heat. The limestone buildings of Sodom and Gomorrah could not have turned to ash with out very extreme heat from sulphur. The white ash found at Gomorrah was tested and found to be calcium sulphate. Calcium sulphate is the by product of limestone, calcium carbonate, and sulphur burning together. Therefore, the ruins of Sodom and Gomorrah prove that these cities were destroyed by burning sulphuric brimstone just like the Bible says.
"And turning the cities of Sodom and Gomorrah into ashes, condemned them to destruction, making them an example to those who afterward would live ungodly." 2 Peter 2:6.
This reminds us of how we should be living in accordance with God's Commandments, because this planet is going to be doomed to destruction for sin and the ways of man.