You must visit this neighborhood if you visit Amsterdam. The area with the girls are narrow streets with some red lights on the doors, that are like cabins. WHen I went (last Christmas), they were cheeky, so I recommend that you have your bags and wallets safe to not be robbed. Some girls were very young but there were older ones and obese ones. Incredible. I recommend to visit the sex shop and the erotic museum where you can find interesting objects at a good price. It´s totally normal to pass by and look. The store of the preservatives (I don´t remember the name, it is very interesting, now I will put up photos.