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How to build shelters in the wild - Wilderness Arena Survival
A shelter can protect you from the sun, insects, wind, rain, snow, hot or cold temperatures, and undesirable observation from others. It can give you a feeling of well-being and help you maintain your will to survive. If in doubt about the importance of shelter, remember the "Rule of Threes": You can survive 3 minutes without air, 3 days without water, 3 weeks without food, and in extreme, harsh environments - only 3 hours without shelter.