Located in southwest Jordan are the ruins of the ancient city of Petra. Massive temples, tombs and monuments have been cut into the surrounding sandstone cliffs. Petra, which is Greek for “rock,” is also known as “the city in the rock.” Perhaps the most impressive Petra structure is the Sik al-Khazneh, also known as the Treasury. It is an elaborately carved and embellished tomb. Besides the decorative tomb facades and monuments, Petra is also known for its highly organized water system, which included ceramic pipes, intricate water channels and cisterns.