Alexander's empire now stretched from the Balkans down to Nubia and across the Punjab. He wanted to reach the "Endless Ocean", that vast expanse of water that the Greeks believed formed the edge of the known world. In his fervour to reach the Endless Ocean, he had miscalculated the mood of his men. Alexander knew, however, that the land just beyond the Ganges River would have been an easy conquest, because a weak, unpopular king ruled it. Trying to make the best of a frustrating situation, Alexander decided to "retreat" via a route that would allow him to conquer all of southern India. Soon thereafter, in 324 bc, Alexander's dearest friend, Hephaestion, died of a high fever in the city of Susa. In modern Iran Alexander is still seen as an evil king—a personification of the devil, in fact—who did his best to destroy the respectable old Persian culture and religion and who put Persepolis to the torch.