Olympiacos Piraeus
Olympiacos Piraeus, or Olympiakos Syndesmos Filathlon Peiraios, is a team from the port city of Piraeus. It is the most successful club in Greek history. And as it happens, the successful ones also have a lot of fans, which is also true here. According to various polls, this is the most popular football club in Greece. Their home stadium, the Karaiskakis Stadium, has a capacity of over 32,000 spectators.
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Red Star Belgrade
Fudbalski klub Crvena zvezda, known as Crvena zvezda Belgrade or CZ Belgrade for short, has been playing football since 1945. Historically, it is the most successful football team in Yugoslavia and subsequently in Serbia. And it didn't just stay with domestic success, they managed to make a name for themselves internationally as well, as they still participate in the Europa League and the more prestigious Champions League.
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