Excerpt:
Time is considered one of our most valuable assets. The keeping of time goes all the way back to the beginning of civilization. Both historians and archeologists believe that stationary and portable sun-dials were probably developed in Egypt or Mesopotamia. The oldest extant sun-dial can be found in Egypt and dates back to 1500 BCE. We know that the early Egyptians used the pyramids as well as the obelisks as a forerunner to the sundial.