What you need when backpacking does not include a stack of guidebooks. You can figure out most everything—public transportation, cheap hostels, the best eats, backpacking tours and can't-miss local events—as you go, and most of the stuff on massive backpacking checklists is actually not necessary. However, if you skimp on any of the following four items, you are asking for trouble:

1. Safety Items: Buried deep within the vast checklists of things you should bring backpacking are the very items that are essential to your own safety and that every advisor recommends you bring. A first-aid kit, personal medications, sunscreen and insect repellent are easily overlooked but absolutely essential items, without which your trip will become quite uncomfortable, if not dangerous. Forget them at your own peril.

2. Personal Documents: Some “checklists” don't even include these items on their "what you need when backpacking" lists—your passport, immunization records, passport photos and emergency contact information—but good luck getting off the plane without your passport or getting the help you need should anything go wrong. Due to the elevated risk of theft during your travels, photocopies of these critical documents are also essential and should be stored separately from the originals.

3. Items For Staying Dry And Warm: Here's where many people start to go crazy with the extra baggage, but all you really need are three rather lightweight items. First, a small, packable umbrella. Experienced backpackers know that, when it rains, it pours, and even the best in waterproof clothing will not keep you completely dry, so why bother? An umbrella will be as effective as a jacket at keeping your torso dry, will protect your pack and is easily stowable. Second, whether a sleeping bag or a thin sleeping bag liner, you will want a clean layer between you and the sheets you are given at a hostel. Some backpackers swear that a sleeping bag is essential, while others seem to get by without this rather bulky item just fine. Finally, you will need a towel, preferably a lightweight, high-performance towel that can absorb many times its own weight.

4. The Right Clothing: Although clothing is essential, be wary of packing too much of it. Most advisors recommend a few t-shirts and a few pairs of light, quick-drying pants. If you can afford it, replace one or both t-shirts with high-performance moisture-wicking shirts that will keep you both warm and dry. Many experts recommend low-rise trail shoes over hiking boots, and nearly everyone recommends some type of lightweight, open sandals for both walking in warm climates and for relaxing in after a long slog in your trail shoes. You'll also want a long-sleeve shirt to protect yourself against bugs and the elements, and it need not be a heavy shirt if you also bring a fleece. Bring four pairs of underwear and socks, and you are set. If you find you are in desperate need of additional clothing during your trip, you can buy it. Pay attention to bring only the essentials of what you need when backpacking and buy the rest when you're on the trip, if you need to.