Chester 's population as of 2011 was less than 100,000 and Cheshire West and Chester had less than 330,000 before 2012 .
With a population of 79,645 in 2011 , it is the most populous settlement of Cheshire West and Chester , which had a population of 329,608 in 2011 , and serves as the unitary authority 's administrative headquarters .
Chester