Coastal regions are a transition zone between land and sea movements. It is exposed to many disasters such as floods because it is a transition zone. In the absence of co-relation between urban development and flood defense systems, it has led to separation in cities. This thesis works on studying nature-based solutions as an integrated flood defense system for the shrinkage of urban developments. This research aims to create a more nature-based flood defense system in the city of Harlingen, using the city center as a pilot area. The main idea is not only to solve the flood risks and shrinkage risks but also to think the city is much more efficient in an economical way and responsible for the coastline, the transition zone area can actually help for the adaptivity and the city itself can also be more resilient.