Boiling or distilling. You can let the water gather in a closed bottle but that takes days. Then again I don't know!

There are two options I know of: 1) Boil the water. Just make a fire and put a pot of water over the fire until it comes to a boil. The problem with this, is that in some places at certain times when it's very dry out, there are fire bans. This means it's illegal to make a fire because it may inadvertently cause a forest fire. 2) Use a hand pump water filter. You can buy portable water filters at any store that sells camping equipment. The one I've used just has a bottle with a pump handle on one end and a tube on the other end. The tube gets placed in the watersource (lake, stream, etc.) and then you pump the water which gets filtered and goes into the bottle. Then you can drink the filtered water out of the bottle! This method does require a lot of effort for not much water though.

You can also use water purification pills, aka iodine pills. This is a nice solution for long camping trips because the pills are light and don't take up too much room in your backpack.

Since you asked about PURIFICATION, a *filter* will not hack it. Purified water and filtered water are two different things. Filtered water has had physical particles removed from it. Any series of successfully fine media (rocks-gravel-sand-fine sand) can filter water. However, any chemical or biological nasties that cannot be trapped by a filter's mechanical process will still be there. Purified water has been filtered and treated to remove the chemicals and kill the biologicals. The only way to purify water without specialized gear (such as a hand-pumped water purifier) is to filter the water as best you can then purify by distillation. A Boy Scout field filter can be made by taking coffee can (metal or plastic) and punching holes in the bottom. place a few layers of tight-weave cloth (I found t-shirts work well) in the bottom and then layer in clean fine sand, clean coarse sand, and clean gravel into the can. Fill the can using a container (this will be your "black water" container, used ONLY to carry unfiltered water) and hang the can over whatever you will use heat the water. Take the filtered water in the second container and boil it. You can catch the rising steam with an inverted dutch oven or other pot lid suspended over the boiling container. Angle the lid to your clean water container (used only to hold filtered, distilled water). Boil until the filtered water is almost gone (no sense in burning a good container) and repeat as needed. If you are 100% sure there isn't chemical contamination of the water source, boil for 5 minutes without bothering to catch the steam. As I really hate getting the runs in the boonies, I'd dose the cooled, boiled water with PortaPure or bleach. If you use PortaPure tablets, follow the directions and invest in the chlorine neutralizer to get rid of the iodine taste. An alternate is plain, UNSCENTED bleach with at least 5% sodium hypochlorate content at a ratio of 5 drops per gallon. Mix well and let sit until the chlorine smell is gone.

Water purification kits sold at sporting goods stores, water purification tablets, or boil the water. I used to live in a third world country and we used to put the tablets in water then soak lettuce, fruit, and vegetables eaten raw in the same water. Worked pretty good (not perfect!).

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