For camping in freezing temperatures, a good down sleeping bag will provide the warmth you need for a comfortable night’s sleep and stop you getting frostbite. Down is compressible, lightweight, and extremely warm, making it perfect for space- and weight-conscious backpackers. Look for high bulking power (measured in cuin) – a higher number here means greater bulking power and therefore higher-quality down. Down sleeping bags are available in oval and mummy shapes. If you’re going to be camping in damp or humid conditions or near water, a synthetic sleeping bag might be a better option; down significantly loses its ability to warm when it’s wet. As always, pay attention to the recommended temperature range when buying.