Double-landlocked countries
There are just two countries that are double-landlocked: Liechtenstein and Uzbekistan. Their unusual claim to fame is that not only are they landlocked with no access to the high seas themselves, but they are also surrounded by countries that are themselves landlocked.
Another way to put it is that you have to cross two national boundaries before you can reach water connected to the oceans.
Growing up on the island of Great Britain I somewhat took for granted that with a few hours in most directions and I’d be looking out onto the sea. But that’s not at all the case if you were born in a landlocked country.