Old Town (Vanalinn) in September

May through September gives you the full experience without frostbite. July brings White Nights when darkness barely shows up, perfect for those midnight wanders through empty medieval streets. But July also brings cruise ship crowds that pack Town Hall Square shoulder-to-shoulder from 10 AM to 4 PM. September hits the sweet spot — warm enough for outdoor dining, cool enough that the crowds thin out, and the autumn light makes those red rooftops absolutely glow. Winter turns Old Town into a Christmas card, but temperatures drop to -10°C and some attractions close completely. The Christmas market in December draws massive crowds but creates genuine magic if you can handle the cold.