The World's Only Underwater Post Office
Did you know Vanuatu has a functioning post office nine feet or three meters under the sea? Since 2003, snorkelers off Hideaway Island have posted special waterproof postcards into an underwater postbox - when postal staff are on duty down there, a flag flies on a float above the site. The box really is cleared and the cards really arrive.
Vanuatu
Greece
Ecuador
Maldives
Iceland
Palau
Zambia