We usually travel when conditions favor our needs and wants. The most popular reasons to visit any special place like Greece are a honeymoon or vacation. Then it depends on what you want to do or experience.
Well, when and what can I do in this Mediterranian mecca. Which region of the country do you want to visit. Of course June to July is the peak time of the year when people visit making it the most crowded. September to April/May is the cheapest, least crowded, and offers a variety of climates. If you don't mind the crowds of both tourists and locals, the warm climate will just melt your heart's desires. If you miss the high peak times, September and October still offer warm climate minus the crowds. The autumn months are more beautiful and relaxed. There's a balance of balmy winds, softer and subtler fragrance in the air to enjoy.
If you prefer a colder climate, November to March lends to crystal clear, wet conditions, and snow covered mountains perfect for skiers. If you're a history buff, these sites will always be busier during the summer months when children are out of school, and family vacations are in full swing. Lodging will be harder to find. Although this time of the year is quieter, many attractions and hotels are closed. Be sure to call ahead to inquire about any discounts that may be available. The food is good anytime of the year because the Greeks have taken pride in their cuisine since the beginning of time. Just beware that when you want authentic Greek food be ready for the real thing. Many times Greek food in tourist areas have been dumbied down to appeal to the touristx' taste buds. If you're on a budget stay away from the larger cities at mealtime. The Euro is the monetary unit of exchange Public transportation is economical whether you travel by train, bus or ferry.
Greece has over 19 million tourist a year because it's one of the most popular regions in the world for tourism. Plan thoroughly and enjoy!