Containers is the third of the 5 Cs. It’s vital that you make space in your kit for the means to heat water, cook, and decoct medicinal remedies. In the pioneering days, cast iron was commonplace. As far as resilience and heat transfer, it’s unparalleled, but it’s extremely heavy, making it a less-than-optimal choice by modern standards.
Stainless steel is probably the best bet for anyone heading into the wild. There are amazingly lightweight titanium options, but they are far less durable and readily warp when exposed to open flame. Anodized aluminum is another fine choice, as far as durability, weight, and heat transferability.
Whatever containers you do decide on, it’s imperative that they can withstand an open flame. You must be able to boil your water so that microbes do not ruin your wilderness experience. Under conditions of cold, having a hot drink can literally be a lifesaver, as warming the body’s core is essential in the event of hypothermia.
A water bottle is an important container, but don’t waste your time with plastic bottles—no matter how trendy the packaging is. The consensus among scientists is that boiling water is the only way to kill water-borne pathogens. A large stainless steel bottle—say, 32 oz—is great. You will need to boil your bottle multiple times a day to stay sufficiently hydrated. A smaller bottle will mean stopping more frequently to boil water. A larger bottle will mean added weight.