Here is the full list of all 41 Ratopia achievements.
Bury a dead to a grave.
Build Merchant Monument.
Reach 100 population
Make trade agreement.
Keep at least 50 upper class for 12 days.
Experienced Winter's end.
Survive a year in Hard difficulty.
Find other cities.
Activate a shrine.
Build a huge monument.
Experienced Autumn's end.
Saves 99,999 Pia.
Reach prosperity level 7
Upper class appeared in the city.
Middle class appeared in the city.
Experienced Summer's end.
Build a rail in the city.
Order soldeirs to escort.
Rest on a Royal Bed
Reach prosperity level 4
Experienced Spring's end.
Build a decorative structure.
Activate a new policy.
Destroy infected's grave.
Research a blueprint.
Assigne a ratizen to a job.
Accept a migrant.
Place a citizen in a group.
Use a loan.
Keep at least 50 middle class for 12 days.
Build Noble Monument.
Produce an equipment
Change the style of the leader
Enter the dungeon
Destroy Weasel Barracks
Supply electricity to the city for the first time.
Assemble a Ratron at the Ratron Assembly Plant
Conquering the Forgotten Mine
Conquering the Barbaric Palace
Build Scientist Monument
Operate more than 30 Ratrons