20ish litre daysack, your recommendations please.

Look at the following brands, they're all excellent and most have range of heritage models

Aiguille Alpine

Lowe Alpine

Gregory

Osprey

Deuter

Vaude

Millican make bags that are more like the one in your image

I would recommend the pack im about to list in the classifieds.  A Osprey Archeon 24 used once or twice top's.

for packs osprey are normally my default go to, however more on the modern technical end of the scale. for those more retro / heritage style packs maybe have a look at brands which often have a more outdoor kit / lifestyle cross over products like patagonia or fjalraven. rab / lowe often do a lot of 'heritage' ranges

We bought a Low Alpine one (can't remember exactly which on it is) that is about 20/22L for dog walking and a bit of shopping etc, that was about £35 from Blacks. I've got a cheapo EuroHike Rush 25l which gets used pretty much six days a week for riding to work and shopping duties. Apart from the net side pockets tearing a bit due to me shoving a slightly too large water bottle in there day in day out it's been holding up well for a year or more so far.

I got the Patagonia Altvia 22L this summer and it's probably the best pack of it's size I've had, including various Osprey models. Good amount of packets without going over the top, and works well whether full or half empty.

we've got a couple of Osprey packs, really pleased with them

As above, I use an Osprey Escapist 25. On offer at Sigma Sports at the moment too

...This one looks quite decent at 90 quid, but I reckon the collective wisdom here will know of some good alternatives. Cheers.

£90 is considered reasonable for a bag just to wander to the pub with?

My £10 Quechua 20L job serves general tramping about with family as well as serving day pack duties on several holidays, seems I need to raise my aspirational sack game.

This is a great little bag for the money

https://www.decathlon.co.uk/p/mountaineering-backpack-22-litres-alpinism-22/_/R-p-178271

I've got an Alpkit Gourdon 20l bag and for £30 it's brilliant - https://alpkit.com/products/gourdon-20-waterproof-backpack

Granted it doesn't have loads of pockets, but it's pretty comfortable.

I got an Altura Thunderstorm last year and it's been great, use it every day for commuting, as an overnight bag for weekends away, and for long-ish day walks. Comes in plain black, or high-vis and grey, which is smarter than it first looks (IMO) so you don't look like 'cyclist' when not on the bike (helped by it wearing well and not looking shabby despite a lot of use).

Pro's - drybag closures are just so much better than zips. Laptop and organizer are surprisingly well thought out for keeping wallet, phone, keys etc accessible.

Cons - it's simple, there's no plethora of external straps and pockets, equally that means no pickpocketing, or places for things to fall out of. It's very simply made, I got it on sale, but for the £70 it usually is, it really should have more comfortably formed straps. It's better than an Alpkit Gourdon because it's got some shape (the gourdon tends to pull my shoulders back when stuffed full), but the hip strap buckles dig in if you don't wear it, and the straps dig into my armpits if I don't do the chest strap up.

I'd recommend it, but I'd also recommend anything like it that improved on the back panel and straps.

I got a Berghaus of  Amazon a few years ago and very happy with it. There's a few on offer just now too

Yep, try a Gourdon.

Much prefer their minimalist approach, find them very comfy and they last if you're not dragging them over rocks.

You can borrow one of ours if you're up our way and try it out.

gourdon is a drybag with some straps glued on and a foam mat stuffed in a pocket. not particularly robust, I snagged one on a branch and it pretty much split in two.

I’ve got an Alpkit Gourdon 20l bag and for £30 it’s brilliant – https://alpkit.com/products/gourdon-20-waterproof-backpack

Granted it doesn’t have loads of pockets, but it’s pretty comfortable.

We also have this bag - it's pretty great for what it is. Seems to hold far more than 20l would let you believe.

Had a Alpkit Gourdon before and that, despite being the same volume, seemed to hold less as had a narrow diameter & smaller aperture  but longer body made it just a bit more awkward to rummage about in / stuff jackets in.

I have had and used many backpacks and I always keep going back to Lowe Alpine stuff, they just fit me, and they do the job very well.

I have a couple of the Alpkit Gourdons, an old 20L and 30L. Great for kit storage and trips etc, but I don't find them all that comfortable.

Fjällräven make traditional looking daysacks. Maybe something in their line-up could work for you.

I would steer clear of "traditional" style and buy something designed to be nice to carry, such as Osprey.

Fjällräven make traditional looking daysacks

That might just work if the OP is a first year student.
Oh hang on,then he would just look the same as every other 1st year#foxpower 😆 🤣

Surely you mean #arcticfox ?

Osprey is always my first call.

They dont always look or feel the best, but then when you use them they are just brilliant and last for ever

I think Gregory are much better than Osprey nowadays but slightly heavier

I would steer clear of “traditional” style and buy something designed to be nice to carry, such as Osprey.

I am looking at a lot of the suggestions, (thanks for taking the time everyone) and thinking that the plain, flat backs and basic straps might not be terribly comfortable, even though I'm unlikely to be carrying a lot of weight. So, you may have a point.

Will update if/when I purchase something.

@tthew - even if you've just got a water bottle, snacks,  flask, cups and an extra layer a bag can get heavy