Most of the major earthquakes on the planet are located on the places where the boundaries of the plates are, or very close to it. Some plate boundaries are more active than the others though, so the intensity of the earthquakes varies from place to place.
The most intense earthquakes seem to appear alongside the so called ''Ring of Fire''. This is actually where the boundary of the Pacific plate is, where this plate is sunducting bellow the plates that surround it. Because the Pacific plate is a massive plate, with its subduction, it causes very big and lot of adjustments into the crust. Because of these constant adjustments, there's earthquakes almost every second in some part of this plate's boundary. Unfortunately, occasionally it causes devastating earthquakes, where lot of people lose their lives and huge material damage is caused as well.
Sparta was known for their extreme war skills and judging by history Athens was a capital city and most of the soldiers of Greece came from Sparta I guess
