Speculum Alchimiae - Alchemical Lab and Subterranean Tunnels

First written references about the stone area at the current location of the museum date back to 900 AD, which means this house is probably the second oldest building in Prague. ...According to written accounts, there was an herbal pharmacy in the 15th century where alchemists sold their potions and elixirs. In the 16th century, the house became a place where Emperor Rudolf II established his alchemical laboratory and invited many famous alchemists to work. ...Alchemical workshops were discovered under the building, and also underground tunnels that connected the three most important places in the city - Prague Castle, the Old Town Hall and Barracks. ...A lot of legends are tied to this house. The most famous tells of a goat’s flaming chariot that used to emerge in front of this house..“ -- Speculum Alchemiae