De Wallen in Amsterdam is the neighborhood known as the Red Light District, characterized by a high concentration of brothels and houses where prostitutes advertise their services from windows facing the street. Prostitution is legal and regulated in this area to ensure the safety of both the workers and customers. The district got its name, which means "the wall," from its location near the old city walls where sailors used to reside. Despite some changes in recent years due to the city council acquiring buildings for other uses, De Wallen still maintains its distinctive features, including the iconic red lighting and windows showcasing prostitutes. Additionally, the Oude Kerk, or old church, is located in the heart of this neighborhood, adding a juxtaposition of religious significance amidst the "sinful" surroundings.