From 1850 to 1941, Portland was considered one of the most dangerous ports in the world. It earned the moniker "Forbidden City of the West" due to the Shanghaiing trade and the white slavery that was carried out there.

The Portland Underground, commonly referred to as the Shanghai Tunnels, was a series of bar and hotel basements linked to each other and to the Willamette River docks by an intricate system of tunnels under the city streets.

These tunnels were used for legitimate practices, such as keeping ships' supplies out of the rain and away from the heavy traffic above. But far more illicit deeds were carried out in the tunnels as well.

The term "Shanghaiing" refers to the capture and sale of able-bodied men to ship-captains in need of extra crew. Victims were either drugged with opiates, kidnapped while intoxicated, or simply knocked unconscious. They were then dropped or dragged into the tunnels through trapdoors called deadfalls. Once in the tunnels, captives were locked in any number of cramped underground cells until they could be sold off to a life of slavery at sea.

Able-bodied men weren't the only people who ran the risk of being Shanghaied. Portland's daughters were also told to avoid certain areas of town, where women were regularly kidnapped and sent to faraway cities to be sold into prostitution.

A simple search will turn up any number of stories about slaves being eaten by starving crews, underground opium dens, humans trafficked under the streets of Portland, and men who returned from sea only to be captured again by clever and brutal Shanghaiers. Fantastic legends abound, but the level of truth in many of these stories remains questionable.

The city's network of tunnels reportedly ran from Old Town/Chinatown and into Downtown Portland, but a great majority of these subterranean spaces have been filled in during various public works projects.

The Cascade Geographic Society conducts tours of a portion of the Portland Underground. But no tunnels that lead directly to the waterfront are known to exist today.

Cascade offers an above-ground lecture on the history of the neighborhood, followed by a below-ground tour showing off remnants of different kinds of group cells, a former opium den, a solitary holding cell for breaking the will of young women, a trap door, and many other dusty spaces and artifacts.

Tours are held every Friday and Saturday evening, on the first Thursday evening of each month, and often on other evening weeknights as well.