Here is the full list of all 20 City Play achievements.
Your City has a basic road system!
You have created a wood cutter!
You have created two forresters!
City population: 50!
Your City has a complex road system!
City population: 100!
Your City has opened its first Market!
You have created two Animal Farms!
City population: 150!
Your City has an advanced road system!
You have a School District!
Your City has a Health System!
Your City is more secure!
Your City has its City Hall!
City population: 250!
City population: 400!
Your City is Green!
City population: 600!
Big City Cultural Life!
Your City is a Metropolis: 1000!