Here is the full list of all 38 Cities: Skylines II achievements.
Reach milestone 20.
Unlock 150 map tiles in a single city.
Build any airport.
Build 10 parks in a single city.
Have at least 1000 citizens and an average happiness rating of 25%.
Have a city that produces electricity by only using renewable energy sources.
Build a city where at least 20% of the population has a university level of education.
Have at least 1000 citizens and a city attractiveness rating of 90.
Have a total loan of at least 200,000 in a single city.
Have a total of 10,000 tourist visits in a single city.
Reach a population of 100,000.
Have 20 active transport lines. These can be passenger or cargo lines or any mix of the two.
Bulldoze a total of 1000 buildings.
Create 10 different districts in a single city and assign policies to each.
Assign a policy to a city district.
Have 6,000 citizens treated at medical clinics or hospitals in a single city.
Build 10 signature buildings in a single city.
Experience all four seasons by building a city in a climate with a snowy winter.
Plant 100 trees or bushes with the landscaping tool in a single city.
Use the photo mode to take a screenshot.
Create a city district and assign a city service to that district.
Have a look at each individual info view panel.
Unlock 50 map tiles in a single city.
Build 5 signature buildings in a single city.
Have at least 1000 citizens and an average happiness rating of 75%.
Reach enough milestones to unlock all city services in a single city.
Have buildings from all four zone types in a single city.
Build city with residential, commercial and industrial zones, water, and electricity.
Unlock each building available in the base game.
Experience a hailstorm.
Experience a tornado.
Experience a forest fire.
Have 5 city policies active simultaneously.
Follow a citizen's lifepath from childhood to old age.
Use the editor to make a map.
Have 50 active transport lines. These can be passenger or cargo lines or any mix of the two.
Use the editor to make an asset of any other type than map.
Build all unique city service buildings in a single city.