I text pictures to my Daddy and share my feelings with him during the journey. When I text the pictures of castles to him, he asks why most of them are built on the top of the hill. I tell him castles like these can be used for defense. As an officer working for Hydrological Power and Engineering Agency, the first question pops in his head is “how do they drink water”. Talking about this, we have to say ancient people were very intelligent. In La Alhambra, the tour guide tells us the first thing the constructors try to solve is the water problem. They built the channel for water drainage which can still work thousand years later. Although La Alhambra is located in a dry area, you will still be impressed by the emerald green tree and shade.