In the story, Golden Lane is a street close to Prague Castle, where alchemists used to live and work. The term alchemy derived from the Ancient Greek word khemia meaning "art of transmuting metals". Alchemy is both a philosophy and an ancient practice which focused on the attempt to change base metals into gold. The practice concentrates on researching the preparation of the "elixir of longevity", and achieving ultimate wisdom. The practical aspect of alchemy generated the basics of modern inorganic chemistry. Alchemy has been practiced in Mesopotamia (comprising much of today's Iraq), Egypt, Persia (today's Iran), India, China, Japan, Korea and in Classical Greece and Rome, in the Post-Islamic Persia, and then in Europe up to the 20th century, in a complex network of schools and philosophical systems spanning at least 2500 years.