I bought this primarily to use as a day bag when traveling in Europe for three weeks. Wanted something big enough to hold a book, water, food, and extra layer, but would also be small enough to pack into a full-size backpack for travel days. This fit the bill. As other people have mentioned, many European museums will let you take a purse(ish) bag inside, but will make you check a backpack (but rules varied from place to place). I was comparing this to several small "messenger bag" style bags and am happy I chose this instead. The size is actually quite nice. The main compartment is a rectangle that can hold quite a bit (e.g. two thick travel guides, food, and two water bottles or two water bottles, one book, one light jacket, and food). Works best when loaded mostly full, but not bulging. If you bulge the sides out, it doesn't ride well, and the front flap doesn't close nicely. The open pocket under the flap isn't very useful, because anything you put in there just subtracts space from the main pocket - I only used it for maps, museum guides and the like. Also, there is an inner zippered compartment, but again, anything stored there subtracts from the main compartment, so not very useful. Also, not accessible when the main compartment is loaded. The advantage of this bag over the typical "messenger bag" is that the pocket on the outside of the front flap is actually useful. It's got at least an inch of depth, so it can hold quite a bit. Camera, chap stick, headphones, nail clippers, Spanish/English dictionary, etc all went in here. The flap has a zipper under the velcro, so it's somewhat secure, but the zipper is not the full width of the flap, so hard to get large items in and out. I have two main gripes with the bag: 1) Color. It's inoffensive, but totally boring. Also, it's the exact same color as my coat. ("Hello, I am Beige Man, and I have come to visit your country.") I actually saw another tourist with the Olive version, and it is actually worse than the beige. (It's just a slightly greenish beige - it isn't any darker than mine.) Would have strongly preferred a darker color. 2) Quality. OK, all of these are acceptable for the price, but some things I noticed: - Main compartment zipper is very stiff. Improved somewhat with use, but is still not free like the other zippers. Unless I was somewhere where theft was a concern, I just started leaving it unzipped. If you have weight in the front pocket, it makes the main pocket difficult to sneak into anyway (advantage of this design over a typical messenger bag). - Velcro doesn't seem lit will last very long. It had a satisfying "rip" when I first got it, but over a month of use that has reduced to a light cling. Good enough to resist a breeze, but I'm not sure it would deter a thief any more.... - Flap stiffener getting creased. The flap over the front pocket has a stiffener in it (probably cardboard) that has gotten creased several times, even though I'm fairly gentle with the bag. The flap doesn't hold its shape like it did initially. (This cardboard is probably also why the bag says it is not machine washable - seems like a very short-sighted design decision....)