Forgot something essential on a camping trip

[Alan]

I left the tent poles at home once, I had all the tent parts except the actual poles. I had to rig something with sticks and rope, it looked ridiculous but it worked. What essential item have you forgotten that ruined or almost ruined a trip?

 

[Spencer]

I once forgot my sleeping pad. The ground stole all my body heat all night. I think I slept an hour.. that pad now goes in the truck first, before anything.

 

[old timer]

 I once forgot my headlamp, and it managed to turn what should have been a simple evening into an absolute mess. It's really amazing how just one small thing can completely throw everything off.

 

[sixth_sense]

I left the tent poles at home once, I had all the tent parts except the actual poles. I had to rig something with sticks and rope, it looked ridiculous but it worked. What essential item have you forgotten that ruined or almost ruined a trip?

Left the ammo once and spent the trip practicing patience instead of shooting.