The world’s two largest ice mailboxes were unveiled at Harbin Ice and Snow World in northeastern Heilongjiang Province, together with a stamp specially designed for the annual event. /VCG Photo

The 2.6m tall ice mailboxes are not just for show, they're functional mailboxes. /VCG Photo

After getting a postcard from the ice-themed post office, it is then stamped and ready to be slotted into the mailbox. Mail carriers from the Harbin City Office of China Post will come to collect all mail for delivery in the evenings. /VCG Photo

According to China News Service, to echo this year’s “Belt and Road Initiative” theme, postcards will be delivered to the embassies of the 65 participant countries. /VCG Photo