This is definitely a case of first impressions made in the snow and loved ever since. The first time I visited Stockholm I arrived on a ferry from Germany that had just made its way across the frozen Baltic Sea, landing in Stockholm after it had just snowed. The Gamla Stan, the old town, the palaces in and around the city, the parks, the streets, the roofs, everything was covered in a thick layer of perfectly white snow, making the already lovely setting of countless islands, canals, bridges, and harbors even more special. While Stockholm is great in summer, with its people enjoying the light, warmth, and the chance to enjoy the water, I have always preferred it in the winter. Maybe because the city is set up for winter, and knows how to make the most of it, while also offering creature comforts and making every place snuggly and warm?
Pro Tip: If you are lucky enough to be there when fresh snow has fallen, head straight out to Drottningholm Palace which is particularly picturesque in the snow.