Seattle Underground

Seattle Underground refers to the underground passageways and former ground floors in downtown Seattle that were created when the streets were raised around 1900. The decision to raise them came after the Great Fire of 1889, in order to prevent flooding from Elliott Bay and to improve the sewer system. Because the new buildings were initially constructed at the old street level, while the streets were later raised by as much as ten meters, the old entrances ended up in basements. The covered-over sidewalks and passageways sat unused for a long time, but over the past few decades they have become a popular tourist attraction that offers a fascinating glimpse into the city's urban history.