Who did the Greeks visit to find out about the future?

Usually the ancient Greeks would visit an oracle in order to take decisions on major issues of the city states. Some of the most famous oracles were the Dodona oracle in Epirus, Delphi in the mainland, Delos the holy island of Apollo, Samothrace the island in the north part of the Aegean sea. Of course the oracle of Amun Ra of Egypt that even Alexander the great visited before he conducted his second battle at Issus.