In many parts of the world, gardens have been created to serve as a retreat. Persian gardens are divided into two crossed axes, forming four quadrants . This symbolizes a belief that the universe is divided by four great rivers.
Irrigation provides formal pools, and fountains add a musical dimension.
High walls and beautiful flower gardens create shade and beauty. This was the design that surrounded the Taj Mahal. As visitors approach the Taj Mahal, they enter through a red sandstone gate that is over 100 feet . It contains etchings from the Koran that were done in black calligraphy. The gate was originally lined with silver, but it was replaced with copper when the silver was stolen in the eighteenth century.