Be warned. Stockholm is one thing above all in December: dark. The sun rises after eight o’clock in the morning, only to disappear again at around 3 pm, and is often obscured all day by clouds. Lucky visitors may get some snow, but December here is decidely cold, wet and dark. That’s why, until the days get noticeably longer again, the city is illuminated for all it’s worth: Central Station, alleyways and the Royal Castle – little lights are lit up everywhere. In Berzelii Park opposite the Kungliga Dramatiska Teatern, the national theatre on the central Nybroplan square, even a herd of life-si…