This is a very helpful guide for making a long term, useful oven. Keep in mind that in a survival situation, all you will need is access to water and just about any clay earth and vegetation, but these ovens will have shorter lifespans and may crack. If you have access to seashells, you could cook them, soak them in water, and crush them to make quicklime and add this with wood ash to your clay and possibly sand to make a crude cement. Overall, this cob instructional/guide is very useful.
How To Build A Cob Oven 2018-08-08
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