Prostitution is legal in the Netherlands, and in Amsterdam most of it is concentrated in the Red Light District. Even if you don't want to play, this is a place you may want to see at night, when the red lights reflect from the canals' inky surfaces. Lots of visitors come here out of curiosity or just for fun. There's no problem with wandering around, and you don't need to worry much about crime as long as you stick to busier streets -- and keep an eye out for pickpockets. Visiting women going around in groups of two or more won't be noticed any more than anyone else, but a single female might be subject to misrepresentation.
The Red Light District, known in Dutch as Rosse Buurt, isn't very big. The easiest way in is on Damstraat, beside the Krasnapolsky Hotel on the Dam. Then stick to the main drag on Oudezijds Voorburgwal, as far north as the Oude Kerk, the venerable Old Church, which stands watch over this passable representation of Sodom and Gomorrah. If you don't mind the weird-looking, sad-sack males and the heroin whores hanging around on the bridges, you can go farther in to the parallel canal, Oudezijds Achterburgwal, and to Nieuwmarkt's cluster of good bars and Chinese restaurants.
In recent years, as part of a continuing effort to clean up the "unsavory" side of Amsterdam, the mayor forced the closure of a third of the red-light windows and bought up properties to be rented as fashion boutiques and other upscale small businesses. Some of the more raucous sex clubs may also be shuttered. And in 2019, group tours were banned from the Red Light district.
Despite this effort, "ladies of ill repute" still populate the many red-fringed window parlors; they're minimally dressed, and tap (or pound) on the windows as potential customers go by. Then there are peep-show joints with private cabins, dark and noisy bars, "theaters" mounting (ouch!) a popular form of performance art, bookstores filled with the illustrated works of specialists in a wide range of interpersonal relationships, video libraries, and dedicated apparel and appliance stores.
For safety's sake, stick to the main streets and the crowds. It's asking for trouble to go off on your own at night down some of those narrow, dark side streets and connecting lanes between the canals -- some are so narrow you literally have to squeeze past other people, and on slow days, hookers come out from behind their windows to turn some of that squeezing into a marketing move. The main streets are usually busy and brightly lit (what with all those red lights and neon signs) and most clubs have security, since they have a vested interest in not having their customers bothered. Remember, though, that the industries active here attract less savory types, including muggers, pickpockets, drug dealers, junkies, street prostitutes, pimps, and weird folks in general. But there are also plenty of tour groups who seem to be having a whale of a time, judging by all the laughing they do as they go around.
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