Coverage is the fourth of the 5 Cs for your wilderness kit. The importance of getting a good night’s sleep where you’re dry, warm, and shielded from the elements cannot be overstated. Knowledge of how to construct various shelters and the best materials to use based on the seasons, climes, and duration of the stay is invaluable—arguably the most important body of knowledge you can take with you into the wilderness.

What material is best for creating a microclimate will depend on the nature of your adventure. One option is a tarp. It’s light and versatile, useful in various seasons and scenarios. It is also waterproof, which has its pros and cons. It keeps moisture out and makes for a great outer wrap for gear, but if water gets inside a shelter, it will collect in puddles on the tarp floor. It also poses challenges for ventilation. It’s not uncommon for people to wake up to a stuffy, humid shelter with condensation collecting on the tarp.

Polypropylene is a synthetic, lightweight option suitable for short stints. It’s inexpensive but does not last long. Silnylon (silicone and nylon blend) is another popular material because it is extremely lightweight and packs well. Shelters made from silnylon are also useful for brief jaunts through the wild, but often fails people on more ambitious ventures. It’s also readily flammable and most silnylon gear uses grommets to anchor the tent, which puts unnecessary stress on the fabric. Better than grommets is interwoven supports that don’t strain or tear the shelter’s fabric when you need it most.

Canvas is an all-around solid bet for shelter. It’s more breathable than a tarp, and modern canvas products are now less susceptible to flame and mildew than ever. It’s a tough material that can handle a beating and thus fares well during long-term treks. Egyptian oilcloth is another excellent choice because it is lightweight, lasts, and can handle a range of weather conditions.

For bedding, most people use sleeping bags, but some of these—particularly down-stuffed varieties—are vulnerable to moisture and mold. If the region to be explored is not humid, however, a sleeping bag works fine. A wool blanket is far and away the best choice for bedding. It’s fire-and moisture-resistant, and retains most of its heat—even if it’s soaking wet. Some people prefer a blend because it’s less coarse, but this is saying “no” to that extra warmth. One hundred percent wool blankets are your best and more affordable bet.