Aegeus, king of Athens, and the sea god Poseidon both slept with Theseus's mother, Aithra, on the same night, supplying Theseus with both divine and royal lineage. Theseus was born in Aithra's home city of Troezen, located in the Peloponnese, but as an adolescent he traveled around the Saronic Gulf via Epidauros, the Isthmus of Corinth, Krommyon, the Megarian Cliffs, and Eleusis before finally reaching Athens. Along the way he encountered and dispatched six legendary brigands notorious for attacking travelers.
Upon arriving in Athens, Theseus was recognized by his stepmother,Medea, who considered him a threat to her power. Medea attempted to dispatch Theseus by poisoning him, conspiring to ambush him with the Pallantidae Giants, and by sending him to face the Marathonian Bull.
Likely the most famous of Theseus's deeds was the slaying of the Minotaur. Athens was forced to pay an annual tribute of seven maidens and seven youths to King Minos of Crete to feed the Minotaur, half man, half bull, that inhabited the labyrinthine palace of Minos at Knossos. Theseus, determined to end Minoan dominance, volunteered to be one of the sacrifices. On Crete, Theseus seduced Minos's daughter, Ariadne, who conspired to help him kill the Minotaur and escape by giving him a ball of yarn to unroll as he moved throughout the labyrinth. Theseus managed to flee Crete with Ariadne, but then abandoned her on the island of Naxos. during the voyage back to Athens. King Aegeus had told Theseus that upon returning to Athens, he was to fly a white sail if he had triumphed over the Minotaur, and to instruct the crew to raise a black sail if he had been killed. Theseus, forgetting his father's direction, flew a black sail as he returned. Aegeus, in his grief, threw himself from the cliff at Cape Sounion into the Aegean, making Theseus the new king of Athens and giving the sea its name.
Theseus embarked on a number of expeditions with his close friend