Which early civilization had the first carefully Planneo cities with sophisticated plumbing?

The Indus Valley Civilization, which flourished around 2500 BCE in present-day Pakistan and northwest India, is known for having the first carefully planned cities with sophisticated Plumbing systems. Cities like Mohenjo-Daro and Harappa featured organized street layouts, standardized brick sizes, and advanced drainage systems that included covered sewers. This level of urban planning and sanitation was unprecedented for its time, reflecting a high degree of social organization and engineering skill.