In one sentence, describe what the following article is about:

If you are worried about the fall of civilization or a bombing, your best bet might be to seek shelter underground.This might be a bunker, bomb shelter, or underground shelter. There are many companies that specialize in custom designing and producing these types of shelters. History has shown that people panic during doomsday-like events like terrorist attacks or bombings. If you want to keep yourself and your family safe, you may want to consider hiding and staying as remote as possible. This type of surviving is often described as “living off the grid,” and is total isolation from society. If you have to escape familiar surroundings, it is important to know how to find shelter from the elements. This includes:  Knowing your local geography in case you have to camp out. Learn about dangerous elements such as land formations and wild animals. Knowing how to make a quick shelter. Depending on your surroundings, you can use nature around you to build a sufficient shelter like a lean-to, that will help protect your body from the elements.

Summary:
Go underground. Stay hidden. Protect yourself from the elements.