How to make baking soda I'm in a place where buying baking soda is proving to be quite difficult*, so I was looking for substitutions, and it seems there really aren't any.  So this got me thinking:  Baking soda is made (or otherwise harvested from nature) in some way.
How can I do this?
I realize the answer is likely to be so involved or expensive that I won't want to undertake the project, but for the determined baker, how would it be done?
*I eventually found some.
NOTE: The question is about making, not sourcing or substituting, baking soda.
Sodium bicarbonate, the chemical name of baking soda, has always been manufactured using industrial processes at an industrial scale. I can't see how it could be practical to make at home. You'd need specialized equipment and you might well find that the materials you need aren't any easier to acquire.

Baking soda is known by different names, in addition to sodium bicarbonate according to Wikipedia it's also known as bread soda, cooking soda, and bicarbonate of soda. So it's possible it's available in your area on under one of these other names. If you live in area where a language other than English is used then you might find other alternative names in that language's version of the Wikipedia page. If you still can't find any you'll either have to pay to have it shipped to you or find a substitute recipe that uses some other leavening agent.