Helsinki enjoys a milder climate than much of Finland thanks to the Baltic Sea and the gentle winds from the Gulf Stream, however, you’ll need to rug up warm in the winter. The most enjoyable months to visit are June through September. In July, local folk flee the city for their summer cottages, and many offices close. It’s a grand time to be a tourist - the weather is pleasant, the markets bustle and the cafes set up their outdoor tables. If you’re interested in culture, book your trip during August, when a major arts festival and countless smaller performances will keep you entertained.