The Harappan civilization, also known as the Indus Valley civilization, flourished in the Bronze Age around 2600 to 1900 BCE in the region that encompasses modern-day Pakistan and northwestern India. The major Harappan cities were characterized by several prominent features:

1. Urban Planning: Harappan cities were remarkably well-planned and displayed a sophisticated urban layout. Streets were laid out in a grid-like pattern, forming a well-organized network. The cities were divided into different sectors, with separate areas for residential, commercial, and administrative purposes.

2. Brick and Stone Architecture: The Harappans were skilled builders and constructed their cities using fired bricks made from mud and stone. The bricks were uniformly sized and used for constructing houses, public buildings, and defensive walls. The use of burnt bricks contributed to the durability and uniformity of the structures.

3. Complex Drainage Systems: One notable feature of Harappan cities was their advanced drainage systems. The cities had well-planned and engineered systems for wastewater management. Houses had individual bathrooms and toilets connected to an underground sewage system. Streets were equipped with covered drains, ensuring efficient disposal of waste and rainwater.

4. Great Bath: Some Harappan cities featured an impressive structure known as the Great Bath. These large, rectangular pools were likely used for ritualistic bathing or other ceremonial purposes. The Great Bath found at the archaeological site of Mohenjo-daro is the most famous example.

5. Citadel and Defensive Walls: The major Harappan cities had a fortified citadel or acropolis located on elevated mounds. These citadels housed public buildings, administrative centers, and possibly the ruling elite. The citadels were often protected by defensive walls, which provided security and protection for the inhabitants.

6. Standardized Weights and Measures: The Harappans had a sophisticated system of weights and measures. Archaeological findings include standardized weights made of stone, terracotta, and faience. This suggests the existence of a well-regulated trade and economic system.

7. Harappan Script: The Harappans developed a script that has not yet been deciphered, known as the Harappan script. This system of writing was found on seals, tablets, and pottery. Despite efforts by scholars, its meaning and content remain unknown, limiting our understanding of Harappan society and culture.

These prominent features demonstrate the advanced urban planning, engineering skills, and social organization of the Harappan cities, reflecting a sophisticated and thriving civilization.