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You can also use the site: https://theescapists.gamepedia.com/
to know how to escape each prison.
There are a total of 10 prisons, you only have to escape out of 7 to get the achievement.
For this achievement you have to escape the "Normal" prisons
Once you have escaped from any prison for the first time you will get the specific achievement for that prison, once you have escaped all 7 "Normal" prisons, this achievement will pop.
The "Normal" Prisons you have to escape from are:
- Centre Perks 2.0
- Rattlesnake Springs
- K.A.P.O.W. Camp
- H.M.P. Offshore
- Fort Tundra (No guide yet) [Solution: https://theescapists.gamepedia.com/Fort_Tundra]
- U.S.S. Anomaly