The event recorded in the Bible known as the destruction of Sodom and Gomorrah was a very big and surreal event, surrounded in many questions, especially regarding the exact sin of the cities; but did the whole thing really happen? Let me start off by putting the destruction of Sodom and Gomorrah according to the Bible into very BASIC summary: Sodom and the surrounding cities by the Dead Sea were considered to be very sinful by God, which in reality were probably no different from other cities of the time (Most large cities were considered to be full of sin of the time, so its easy to justify its destruction by God by saying it was sinful). God decided to destroy the cities for their wickedness, but spare Lot and his family, along with the city of Zeboim, so he sends angels to warn Lot of the upcoming danger. Lot and his family flee the city while its being destroyed by God who sends fire and brimstone from the sky onto the cities. His wife, going against the warning of the Angels, turns back to look at the city being destroyed, and turns into a pillar of salt. Reading that makes you think "Did that really happen?"
I read that one of the greatest sins that a person could commit in those times was to deny hospitality to a traveler or wanderer. To refuse to open your door to one who came to you for help was a great sin. People were supposed to welcome strangers with great warmth and kindness. They were to offer their guests everything they had, the best of what they had, up to and including a bed for the night, perhaps even with a woman in that bed, if requested.
Both city's Sodom & Gomorra are known for sexual immorality along with homosexuality but there were more sins than that, I will let the Creator God Almighty tell you himself through his Holy Writ. =====================================As surely as I live, says the Sovereign L ord , Sodom and her daughters were never as wicked as you and your daughters. Sodom?s sins were pride, gluttony, and laziness, while the poor and needy suffered outside her door. She was proud and committed detestable sins, so I wiped her out, as you have seen. (Ezekiel 16:48-50 NLT)