Door 17: Dec. 21 – Winter Solstice (Yule / Yaldā Night / Dongzhi / Soyal)
Tasks - TBA. These haven't been revealed, yet.
Book: Read a book that takes place in December, with ice or snow on the cover, where all events take place in a single day or night, that revolves around the solstice, set in Persia / Iran, China or the American Southwest or prominently featuring Persian / Iranian, Chinese or Native American characters, or a collection of poetry.
I have read An English Murder by Cyril Hare for this task, and it was jolly good fun.