In the simplest possible terms, Free Ports are designated areas around a commercial port into which imports can enter without paying tariffs until and unless they move deeper into the country.
The advantage of a Free Port is factories and warehouses located inside it don't have to undergo customs or pay tariffs on their inputs.
It pushes back a country's customs borders to the point where they only start once your stuff leaves the Port area.
Well, let's say you build a car factory inside a Free Port.
Normally, you'd have to fill out forms & pay a tariff on the steel and components you ship in to make your vehicle, but inside a Free Port the steel and parts can come in tariff free.
Only if you happen to be living in one (you probably won't).
Goods existing a Free Port into the rest of the country still have to pay tariffs & go through normal customs.
No, if anything they may make it worse.
If say, Belfast is a Free Port, then not only will goods crossing from NI into RoI still need to be checked (and vice versa) but so will any goods existing Belfast into the UK (inc NI).
I believe @SamuelMarcLowe has also done a lot of thinking on this, but then I assume he's done a lot of thinking on everything.
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