Although the City of Light is magical all year round, summer is the most popular (and priciest) time to come. As recently as five years ago, Paris was largely deserted in August when locals fled to the coast or countryside, leaving a wake of closed shops and restaurants. But today it remains very much alive throughout the summer, with outdoor music festivals, open-air movie screenings, and fun activities like those available at the popular Paris Plage, the "beach" on the Right Bank of the Seine.
Nevertheless, the city is perhaps most appealing in late spring and early fall. June, when long, warm days translate into extended hours of sightseeing (the sun doesn’t set until 10 pm), is particularly gorgeous. Ditto for September, which promises temperate weather, saner rates, and cultural events timed for the rentrée (or return), signifying the end of summer vacation. In the third weekend in September, scores of national buildings that are normally closed to the public open for visits during the annual Journées du Patrimoine (Patrimony Days).
Winter can be dark and cold, but it's also the best time to find cheap airfares and hotel deals. Spring tends to remain damp and chilly into May, when prices start rising in synch with the mercury in local thermometers.