Amsterdam is famous for the infamous Red Light District. While walking along two canals plus side alleys, you will pass more than 350 windows in centuries-old buildings. Behind the glass are women of every size and nationality offering their services. Red windows indicate heterosexual. Blue windows signal transgender. Along the way you will encounter peep shows, live sex theaters, sex shops, sex-related museums and plenty of bars. The Red Light District is filled with curious tourists and patrolled by police and bouncers, so is generally safe even at night. You can also join a tour. Two key restrictions are no street drinking and no photos of the women. De Wallen began in the 16th century to serve sailors looking for short-term affection. For generations, prostitution was tolerated and not prosecuted. In 2000, non-street prostitution became legal and required sex workers to pay taxes.