On a cherry-blossom blessed curve of Yokohama's Ooka River lies Koganecho — the town of gold. For the past 60 years, however, this alluring name has felt like a bad joke to local residents.

In World War II, American B-29s bombed the area flat, and the black market that sprang from the rubble quickly became teamed with narcotics and prostitution. During the 1950s, American bebop pianist Hampton Hawes and the father of the Beatniks, William S. Burroughs, extolled the potency of the area's drugs, while director Akira Kurosawa chose Koganecho to depict the evils of heroin in his 1963 thriller, "High and Low."

Although the drug trade was stamped out in the late 1960s, prostitution boomed and, by the beginning of the 21st century, the area had more than 150 tiny chon-no-ma (one-woman brothels) — the majority of which were worked by women from developing countries. This was not the type of international image that Yokohama was hoping to project in 2009 during celebrations to mark the 150th anniversary of the opening of its port. So in January 2005, the police launched "Operation Bai-bai" to clean up the area once and for all.