I have a flight to Thessaloniki on August (17 days): what places do you recommend?

Thessaloniki is a beautiful city , and small you can probably see the most important sights in two or three days . You can find the best greek souvlaki there and also don't forget to visit Terkenlis bakery , it's famous for it's loaf and desserts :) . You should enjoy taking long walks by the magical seaside and also go shopping . There are some great traditional markets you could visit ... http://www.holiday-in-athens.com/thessaloniki/sights-of-thessaloni/ -> those are some of the most important historical sights . Visiting Halkidiki is a great idea , it's only a 1 hour drive approximately and it's full of amazing crystal clear beaches :)