Nancy is worth visiting year-round, but spring and early summer (April to June) are the best months — the chestnut-lined squares are in leaf, the outdoor cafe terraces open, and the light is good. The city is relatively uncrowded compared to more obvious French tourist destinations.
July and August bring more visitors, but Nancy never gets as overwhelmed as Alsace or Provence. The market and the main sights operate normally through summer. Autumn brings mirabelle plum season (the city's most famous product) in August and September, and the Fêtes de la Mirabelle in late summer is the year's main local festival. Winter is cold and grey but the Christmas market on Place Stanislas is one of the better ones in the region.