In the real story of mermaids, they are considered a product of human imagination. Sailors in the past might have mistaken manatees or dugongs for mermaids from a distance. These large, slow - moving sea mammals could seem like a mermaid - like figure when glimpsed briefly. Also, the idea of mermaids has been a symbol in many cultures, representing beauty, mystery, and the unknown of the ocean. But again, there is no factual basis for the existence of actual mermaids.
No, Poseidon was a mythological character. Greek myths like those involving Poseidon were ways for people to imagine and understand things they couldn't explain through ordinary means. They weren't real historical accounts.
Athena is not a real story. She exists within the realm of mythology, which often uses symbolic and imaginative elements to convey cultural and moral values, not to recount factual events.
Well, the Atlantis story is considered more of a legend. Despite many theories and searches, no conclusive proof has emerged to confirm it as a real place. It might have been inspired by real events but exaggerated over time.