Access to clean water is a must, but other factors come into play as well. Raising livestock is an effective way to gain reliable access to not only meat, but eggs, milk, and fur as well.
Knowledge in medicine, firearms, building and self defense will all come in handy in life after the end of the world.
In this infographic, National Geographic looks at the best way to prep for the end of the world as we know it.
Source: National Geographic