Salami holds up well backpacking and so do certain kinds of cheeses.  I also like the tuna packets with crackers like @SILHiker, but that can get messy and smelly backpacking. My other go to backpacking snack is almonds mixed with craisins.  You can make any kind of nuts/berries combo you like, it is easy and a satisfying lunch.  Have fun on your trip!

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