From the World Heritage inscription:
The Ligurian coast between Cinque Terre and Portovenere is a cultural landscape of great scenic and cultural value. The layout and disposition of the small towns and the shaping of the surrounding landscape, overcoming the disadvantages of a steep, uneven terrain, encapsulate the continuous history of human settlement in this region over the past millennium.
The towns of Cinque Terra are just beautiful. If you are ever in the neighborhood of Pisa or Genoa, you should consider making a trip there. You can visit the five towns by train, by boat or even on foot. It was the highlight of my recent cruise around Italy and would highly recommend it to anyone visiting Italy. It might not be as sexy as some of the other destinations in Italy like Rome, Florence or Venice, but it has its own unique charm. Try to avoid arriving on a day with cruise ships or show up before 10am or after 1pm to beat the crowds.
View my complete list of UNESCO World Heritage Sites