>>1174653sounds like a good trip OP, I don't really know much about Europe so I don't know what kind of terrain or river flows you will be dealing with. though July should be calmer with lower runoffs.
>What distance would you suggest to paddle with less fit girls?down river 60-80km a day is quite doable
up river 5-15km a day, if it's a shallow river you can pole up (expect to portage if its fast water)
lake 20-40km a day, lakes can be windy and with my luck i am always working against the wind.
>What about the meals?bring lots of snack food, trail mix, jerky, dried fruit, that will be easy to eat on the boat. nice thing with a canoe is it can carry lots of gear so you can feast when you get to shore. bring more food than you think you need because you will burn a lot of calories paddling all day. do research if the river water is drinkable (perhaps with boiling a proper filter or tablets) some rivers and lakes are to pouted for these filters and shit. if you can drink the water that will save you a lot of weight.
stay hydrated!
>Would you let the canoes on the river bank while you are hiking in the woods?yep, just pull it up a bit and flip it over. bring a long bike lock if you are worried about people ripping it off but that won't protect your gear
the shape of the canoe is also worth considering, round bottom is much faster and more maneuverable but tippier. Can be a handfull in white water if you are unprepared, and or can't get low in the boat. flat bottom is slower but MUCH more stable and can be loaded up a bit more. very stable even in white water but maybe a little harder to maneuver into the best line through the chop. you could still end up going for a ride.
spent some time in this boat last summer, good times and you can bring enough gear to be comfortable while camping.
Bring extra shoes and socks, you will get wet!