Amsterdam only exists because is planned. The canal system in Amsterdam is the result of successful urban planning with the execution of hydraulic engineering works with defensive and transport purposes since the city expanded during the 16th century. In Amsterdam, public space is cleverly planned. Among the reasons for bicycle culture are the flat terrain of the city (and the country as a whole) and the freedom of traffic, since the road rules are considered more as suggestions than as rules themselves. The Amsterdam 2025 mobility plan was designed to prevent the growth of car use, improve the public transport network, and increase the number of walking dislocations and by bicycle. To evaluate urban organization and sustainability, The Economist magazine, in partnership with Siemens, conducted a study to identify the greenest cities in Europe. In this ranking, Amsterdam is the 5th most sustainable city in the world.