Alexandria was founded by Alexander the Great in April 331 BC. Alexander visited the oracle of Zeus-Amun at the Siwa Oasis in the Libyan desert to ask the god where to found a city bearing his name. The “god of the ram’s horn” appeared in his sleep and told him to build the city above the island of Proteus. Accordingly, Alexander returned to the shores of the Mediterranean and landed on the site of the present city. He marked out the main parts of the city and the sanctuaries of the gods (Greek and Egyptian). He also wanted to indicate the line of the city wall but had nothing to mark the ground with. An architect suggested using the grain reserved for the soldiers’ meal. The king agreed and marked out the circumference of the city wall. Alexander then offered sacrifices over the plan and received a favourable omen. His principal seer also agreed with the ruling of the gods and indicated that the city would be prosperous in every way.