The walls were built for various reasons, which are discussed below:

Protection against invaders
One of the primary reasons for building walls was to protect the city against invaders. During ancient times, the cities were vulnerable to attacks from enemies, and the walls were built to provide a defense mechanism against the invaders. The walls were constructed around the city, making it difficult for the enemies to enter.

Security and safety
The walls also served the purpose of providing security and safety to the residents of the city. The walls had gates that were closed at night, making it difficult for thieves and attackers to enter the city. The walls also provided a sense of security to the people, knowing that they were safe from any external threats.

Controlled entry and exit
The walls had gates that could be controlled by the city authorities. The gates were opened and closed at specific times, allowing the authorities to monitor who entered and left the city. This helped in controlling the movement of people and goods in and out of the city.

Symbol of power and status
The walls were also a symbol of power and status for the city. A well-built and fortified wall demonstrated the strength and power of the city. The walls also served as a statement of the city's cultural and historical significance.

Conclusion
In summary, the walls were built for various reasons, including protection against invaders, security, controlled entry and exit, and as a symbol of power and status. These walls were an essential part of the city's infrastructure during ancient times and played a significant role in shaping the culture and history of the city.

These wall build for fortification .
Fortifications means -A defencive wall to protect a city , a town etc .