Seattle Underground (Pioneer Square street level raised after 1889 fire)

After the Great Seattle Fire of 1889, large sections of central Pioneer Square were rebuilt with streets raised one to two stories above original grade; original storefronts and sidewalks remain below the modern street level. The Seattle Underground Tour explores preserved basements, passages, and utility conduits that were once the ground-floor of 19th-century Seattle. The underground spaces document the city's deliberate regrading and filling to resolve sewer and drainage problems and to create a new street level. Archaeological and architectural evidence in these subterranean areas shows how the urban landscape was physically altered during reconstruction.