It's hard to say whether Osprey's Porter 30 Backpack is more of a backpack or duffel bag. As a backpack, the Porter can carry a day's worth of trail essentials for long hikes. As a duffel, the Porter is easily carried through airports during quick weekend getaways. Multiple zippered access points to the main compartment allow for easy access whether you have the Porter as a pack or a bag. The Porter's massive pocket configuration includes a dedicated sleeve for laptops, a front organizer for travel documents, and a zippered top pocket for easy access to liquids.