Did you know that the Indus Valley Civilization, one of the world's oldest civilizations, existed around 3300-1300 BCE in what is now modern-day Pakistan and northwest India? It was known for its advanced city planning, with streets laid out in grids and sophisticated drainage systems. Another fascinating ancient civilization is the Maya, who thrived in present-day Mexico and Central America from 2000 BCE to 900 CE. The Maya were skilled astronomers, developing a highly accurate calendar system that was more precise than the one used in Europe at the time. Moving to Mesopotamia, the Sumerians are credited with creating the world's first writing system called cuneiform around 3200 BCE. This system used wedge-shaped symbols impressed on clay tablets and was used for record-keeping and communication. Lastly, the Ancient Egyptians, known for their remarkable achievements in architecture and engineering, built the Great Pyramid of Giza around 2560 BCE. This incredible structure was the tallest man-made building in the world for over 3,800 years. These ancient civilizations left a lasting impact on the world through their advancements in various fields, shaping the course of human history. Their legacies can still be seen in modern-day society in areas such as mathematics, astronomy, and architecture.