A video published by Wendover Productions shows a guide to understanding the essentials of maritime law.
The official line of territory off the coast of any country is shown to be 12 nautical miles and within this distance the rules of the country apply fully.
There is a further 12 nautical miles called ‘the Contiguous Zone’, in which countries may enforce laws that relate to pollution, immigration, customs and taxes.
The 200 nautical miles off a coastline is the Exclusive Economic Zone (EEZ), which is technically international waters, but only the country that owns the EEZ may harvest its natural resources.
Even within the territorial waters, a vessel may pass as long as it is doing so for passage alone, and cannot stop on the coast.
When countries are less than 400 nautical miles from each other, it is between them to decide at what point the territories split.