It never fails. Before heading out to a national park, my wife and I always remind each other to grab the birding guide. And we always forget it. Which raises a question: What item do you always make sure is in your duffel for your national park trips?
Is it a bird book? Plant identification guide? Pair of binoculars? Hiking sticks?
What indispensable item do you make sure to pack for your treks to national parks?