The Dutch constructed an ingenious water management mechanism in the form of windmills way back in the Middle ages that has the kept the soil dry. In a constant struggle between nature and humankind, without these windmills, some 40% of the Netherlands would be under water! They were granted the UNESCO world heritage status in 1997 to celebrate their presence as a monument to the history of mankind. Today, electric and diesel-powered hydraulic systems are in place, but these windmills still continue to do their job through the pure force of wind.