I'll second wraps any day. They're easy to make in camp in the am, travel well, and generate very minimal microtrash as opposed to sandwiches which always seem to have a piece of something falling out of them. Also I'd add apples or some fresh fruit to the above ideas. Another thing if it's going to be hot is PB&J or cream cheese and jam wraps.
have a great trip!
Nothing in the world is more yielding and gentle than water. Yet it has no equal for conquering the resistant and tough. The flexible can overcome the unbending; the soft can overcome the hard. - Lao Tse