The famous ancient Greek city-state known for its military prowess is Sparta. Renowned for its disciplined warriors and rigorous training, Sparta focused heavily on military preparedness and education. The Spartan society was centered around the agoge, a stringent training regimen for male citizens, emphasizing physical fitness, discipline, and loyalty to the state. Their military strategy included a powerful hoplite army known for its effectiveness in battle, particularly during key conflicts like the Battle of Thermopylae. Sparta's unique societal structure and emphasis on martial virtues made it a dominant force in ancient Greece.