Just curious, is it ever mentioned where salt production is done in westeros and essos? It seems like it got overlooked in the world building because it wasn’t really mentioned in woiaf. I was guessing dorne would be a pretty important producer and possibly the disputed lands? It would help explain some of the wealth the Martells seem to have, beyond spices and luxury goods. Just wanted to know if you had any thoughts?

Overlooked? We have a direct example of its production in Saltpans – that’s an example of salt production through evaporation of brine in a shallow open pan. 

Anywhere by the sea could produce salt, so I don’t think that necessarily points to Dorne or the Disputed Lands. Yes, living in a hot climate makes evaporation quicker, but unless there are large amounts of sedimentary deposits allowing for large-scale mining of salt, I don’t see why those would be important producers.