I also strongly recommend taking several short "shakedown" trips before your long trip. Even a weekend at a local state park (car-camping with your backpacking gear, but hiking during the day with full backpack) will be beneficial. You could even camp in the backyard (yours or a borrowed one). Some of those "trial runs" should be during bad weather so you learn how to cope with it and stay dry and warm. The experience you gain from these short trips will make your 70-miler far more enjoyable.

Have you read the articles on gear selection and other topics, and the gear lists on the home page of this site, left hand column? They will provide a lot of the answers you need.

Without far more information, we really can't recommend a backpack size. Where are you are going and what are the conditions there (climate, temperature, trail surface, etc.)? That determines the specific gear you need. How much time do you expect the trip to take? That determines the amount of food and fuel you need to carry. What is the volume of your gear? You can stuff it into a box, measure the space and calculate the cubic inches. 1 liter is approximately 60 cubic inches. Be sure to include the volume of the food and fuel you'll need, plus the amount of water you'll need to carry at one time.

It's generally recommended to postpone buying the backpack until you have the rest of your gear. That's because the pack must fit you, must fit your gear and must be comfortable for you with your gear packed inside (which carries far differently than the sandbags and weights they use in a store). There is also no industry standard for backpack volume, another reason for getting the rest of your gear first. Your gear may measure 60 liters, but there's no guarantee that a "60 liter" pack will hold it.

Backpack fit is almost as personal as shoe fit. For this reason, it's highly unlikely that you and your friend can comfortably exchange packs.

My personal experience is that I can comfortably fit all my gear, food and fuel for a 10-day trip in a 40-liter pack. My gear is probably more compact than most, though. And I don't backpack in desert areas where carrying a lot of water is required.





Edited by OregonMouse (04/19/14 01:23 PM)
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May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey