One of the world’s largest collections of Hermetic, alchemical, and esoteric texts, housed in a 17th-century canal house in Amsterdam and open to the public via themed guided tours (alchemy, magic, witchcraft, Rosicrucianism). Thousands of manuscripts have been digitized and are free to read online, but the visit is the point — you don’t get to touch the books, but you can smell ones that are five centuries old.