Okuiya Niju Kazurabashi Bridge refers to two old (800 years) vine suspension bridges located hidden deep away in the Iyadani valley in Tokushima prefecture used to cross the Iyagawa river. The surrounding wooded area and rocky river are beautiful in themselves, but actually being able to cross these old bridges made with vines is quite the adrenaline rush. It really creaks and sways when people walk on it, and the gaps between the planks of the bridge will get your heart racing. However, the bridges do contain hidden steel cables within the vines and are rebuilt every three years for safety.