The Vanuatu Post mail box stands near the rim of Mount Yasur's crater on Tanna Island, in the South Pacific Ocean, and is the only post box in the world to be positioned on an active volcano.Mount Yasur is estimated to erupt up to 20 times an hour, with it's frequent explosions throwing lava showers of more than 1,000C hundreds of feet into the air.The volcano, which has three vents, is constantly rumbling and causing the ground to shake which makes for a perilous postal experience for both visitors and the postmen who collect mail daily.Photographer Christina Czybik visited the volcano and posted some cards before taking a treacherous walk to the top.The 35-year-old, from Hamburg, Germany said: 'As we approached the volcano the landscape suddenly changed from luscious green jungle to rocks and grey ash. 'It almost felt like we were on the surface of the moon.'As soon as I stopped at the foot of the volcano I felt a rumbling followed by what appeared to be an explosion.'I put some post cards into the box and had to sign a liability waiver before taking the small path up to the top of the volcano.'It was one of the most scary and breathtaking experiences I have ever had.'(dailymail.co.uk)Bakudaily.az