by davekeiller » Fri May 07, 2021 7:15 pm
By a travel backpack do you mean a rucksack for backpacking that you're going to wear all day, or do you mean something more like a holdall that has rucksack straps to make it easier to carry for comparatively short distances?
If it's the former, then I've been happy with my Lowe Alpine sack. For a multi-day trip I'd generally go for 65l, but it very much depends on how much kit you're carrying. Are you self sufficient for 5 days carrying food, tent, stove and fuel? Or are you using hostels etc. so you only need sleeping bag, clothes and day kit? If the former, 50l might well be too small, but if the latter could well be about right.
It is absolutely essential that you try a rucksack on in store, preferably with weight in it. I tried various sacks on before buying my current one, and found that Berghaus and Osprey didn't fit my back properly.