Why did Athens have the strongest navy in ancient Greece?

Answer 1

It relied on two major assets -

the walls which protected the city and the link to the seaport, which allowed them to withstand a siege and import food.

its war fleet which allowed them to harass opposing cities and protect supply ships.

Answer 2

When a particularly rich vein of silver was found in the Athenian mines at Laurium, it was intended to divide the spoils amongst the citizens. The magistrate Themistocles persuaded them, in view of the Persian intent to punish them and appoint a tyrant to rule them after Athens had defeated a Persian force at Marathon five years earlier, to invest the money in a strong navy to resist this. A hundred warships were built and later a second hundred.

This fleet formed the backbone of the combined Greek city navies when it defeated the Persians at Salamis in 480 BCE. After the Persian invasion was turned back, Athens formed the Delian League from the threatened cities to oppose further Persian attempts. This defence was built around the Athenian fleet, which was financed from contributions by the cities.

After peace was made with Persia in 449 BCE, Athens continued to collect the money from the cities to pay for the fleet, and used the fleet to extort the money from reluctant cities. This money paid for the fleet, and the fleet collected the money. This continued until the Athenian fleet was destroyed at Aigospotamai in 405 BCE.

Without its fleet, Athens was stripped of the empire it had created with its naval power, and became a second rate power without the money to continue its high living and ability to intimidate the other cities..

Answer 3

Athens was involved in many wars over several hundred years. Which war are you asking about.