I’ve a pannier rack as opposed the panniers, just the one off the seat post, plan is to attached everything to the bike in dry sacks and velcor straps that we are adapting! So sleeping bag, cooker etc on the bike, then ust a few bits in the backpack. Thin I might go a little larger than 10 liters just to be on the safe side, like someone said, I don’t need to fill it all up
As I presumed then, having read the OP, apparently unlike the smartarses above
some tools, presumably pump and spare tubes strapped to frame
wallet
camera
spork – better than fumblin in pannier
multi tool, for instance leatherman
windproof for fast access
head torch, rear lights
bog roll and dog poop bags (carry it out)
minimal toiletries, if multi day trip
first aid kit
whistle
Pic above is everything on back, this is everything on bike…
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