Holland is a hugely populated area where up to 60% of the residents stay in the coastal area's of the country. Holland is bordered by Belgium, Germany and the mighty North Sea. The low lying area of the Dutch coastal zone makes it vulnerable to natural defense erosion which can cause flooding during storms and with the effects of global warming see levels are rising, The Dutch have tackled the problem and have built the biggest and most extensive coastal defense systems in the world in which dams, and dikes protect nearly one half of the 451 kilometers (280miles) of the coastline. If you ever travel by ferry crossing to Holland you can see the extent the Dutch have went to protect there land against the ever violent North Sea.