The Jewish quarter of Amsterdam - Jordaan - was built in early 17th century. The population increase during the next centuries was enormously, caused by the stream political refugees like protestant Fleming, Spanish and Portuguese Jews and French Huguenots who mainly settled in the Jordaan. The entire area was one ghetto with open sewers, canals served for both transport and sewer, and no running water. Now it is one of the most picturesque and attractive old quarters of Amsterdam.