Sandwiches and hiking don't really go together, since the bread inevitably gets squished and the fillings get mushy banging around in your back pack. Tortillas and pita bread can survive, but it's better if you assemble on site.
It's even better if you can choose from everyone's snacks to fill the pita--hummus, salami, avocado, and carrots. It may sound weird, but it was awesome. And what a view!