Depending upon the context of your dream the boundary wall of a city may signify the president, billionaire, common people, religious powers, peace, victory and manageability of affairs, durability of works. To dream that you have entered into a city wall then it may symbolize that you will be perfect in your religion and will be able to acquire divinity. To dream that you are motionless in a city walls then it may of a sign of your services for the president and getting benefits and goodness from him.