Original: In 1996, UNESCO declared the town a World Heritage Site, and in 2004 the entire valley, the Val d'Orcia, was included on the list of UNESCO's World Cultural Landscapes.
Simplified: In 1996, UNESCO put the town his list as a World Heritage Site, and in 2004 the all valley, the Val d'Orcia, was put on the list of UNESCO's World Cultural Landscapes.