The Black Eggs of Owakudani

The black eggs of Owakudani are usually cooked in the sulphurous waters of Owakudani , hence the black color of their shells, but on inside you have just an ordinary boiled egg. It's interesting that they have a small set of strings and pulleys to bring the boxes of eggs from the base station to the sulphurous water area to cook them there. According to the legend for each egg you eat, your longevity increases by seven years.