The day has been relatively without any major mishaps except the few times one slipped and slid down the mountain slope. But weariness has caught on. The mountain sides are slowly being swept by an eerie grey stillness. The camping sites come to sight. There is another burst of energy that comes to push you into the vicinity of the camping site. The dinner must be cooking. May be a wash in the mountain stream to wash away the dust will be good. The thought of finally sliding into the sleeping bag for its warmth was just too enticing.

It is not practical to carry with you a bed when you go camping, trekking, hiking or mountaineering. A sleeping bag is an improvised bed for you to sleep in designed to be carried by you wherever you go. It is a protective bag resembling a blanket with a zipper. It provides the softness of a bed with the soft padding. It keeps you warm with its thermal insulation. There are two types of sleeping bag. The first is the one that looks like a blanket fitted with, on one side or on both side, with a zipper. This can be folded, rolled up and bound with cords or straps and carried in your backpack. The second is the mummy bag as it resembles a mummy. It is broad on the head side and tapers as it goes to the leg side. But this cannot be folded nor can it be easily rolled. It is better stuffed into the compression sack or the stuff sack and carried in your backpack.

There are a variety of sleeping bags that you can buy in the market differing in their water withstanding capacity and insulation capacity. The Marmot Hydrogen 30 sleeping bag is an example of a mummy bag that keeps you comfortable at 30 Fahrenheit.

The sleeping bags have different capacities in its water absorption capacity, insulation capacity and heat retention capacity. The insulation is faster with the synthetic fill sleeping bag and it is warm even when the bag is wet. Its disadvantage is that it is not easily compressed and so takes up more space in the backpack. The lighter down fill bag though having lesser insulation capacity is able to retain more heat.