Golden Lane was built by soldiers who were working in the defence wall on the northern side of the Prague Castle. They were allowed to build their humble dwellings in the arches of the wall, which was convenient for their occupation. Later they were rented to independent goldsmiths. That's where the original name name, Goldsmith's Lane, comes from.
According to the popular legend, however, Golden Lane received its name from the Alchemists who used to inhabit it. Alchemy was a predecessor of modern Chemistry. Among the alchemist's tasks was trying to make gold from lead. That is why Golden Lane was wronly assumed to be home for Medieval Alchemists.
Nowadays, Golden Lane is open for visits with a Prague Castle ticket and has multiple exhibitions and stores in its houses. The upper gallery of the archers displays medieval armour and torture devices.