Respuesta :

Athens had the strongest Navy and Sparta had the strongest Army.
Athens is very smart so it is hard for the Spartans to defeat them because the Spartans can't get close to the Athenians without the Athenians thinking of a plan. But, I am pretty sure that Sparta defeated Athens in the  Peloponnesian War. That was probably the only time one of them defeated the other.
  
                                                Hope That Helped,
                                                                   19jr1