Cities were formed in specific, once natural settings. For Berlin, it has grown and shrunk in the recent past, and it is once again growing at a rate of about 50 000 people a year/ 500 000 per decade. However, the city elements like geographical situation, transportation, industrial zones, and vacant area obstacle the city expansion at a certain degree.
Westhafen is an old port serving Berlin since 1923 and located at the northwest boundary of berlin inner city. With the metropolitan of Berlin, the site is separated by river and railway lines which make it as an isolated island.
To fix the city fabric and expand the city sprawl of Berlin, the concept is to “link in” the site to the surroundings. First, focusing on improving the transportation situation. Rising the railway lines up as a viaduct and crossing the river with several connected bridges as well. Then, Green infrastructure is leaded into the site along the river as another “link in” element to connect the surrounding parks, forming a green network. Finally, based on the convenient metro system of Westhafen, land use system served as the third “link in” element to define Westhafen as a future hub to stimulate the development of surroundings so that to solve the increase of Berlin population in the future partly.