Hydra, a charming island in the Saronic group, is a must-visit for those who love art, culture, and history. Its unique trait is that cars and other motor vehicles are not allowed; all transportation is done on foot, by boat or donkey. Its picturesque harbor, crisscrossed with cobblestone streets, is brimming with boutique shops, cafes, and art galleries. The island is also famous for artists, poets, and writers it attracted, including Leonard Cohen.