Halter/lead rope (I don't like halter/bridle combos
Small can of Deep Woods OFF! For the horse and myself.
Cell phone, which was non-existant In The Old Days.
Enough water that my horse has a bottle in case I can't find clean water for him. I love him to pieces but, I'm not drinking after him
One hard salami sandwich/muenster cheese on rye bread.
Spare reins (made from binder twine) with quick release snaps. I don't cry about giving them away if someone else has a rein emergency
A few dollars just in case I come out on a road with a general store.
Pistol if I am by myself.
I count myself very lucky that, in more than 50 years of trail riding I have never needed any first aid for the horse or myself while out on the trail. We've done some pretty rough riding. I know there have been some scrapes and bruises but nothing stands out in my memory as life-threatening that I should have been carrying wraps and meds.