13 suspension bridges made of mountain vines (kazurabashi) used to exist in the Iya Valley and provided a vital means of getting people and goods across the river in the past. Two of the surviving bridges still stand side by side deep in the inner valley. They are known as the Oku-Iya Kazurabashi (奥祖谷二重かずら橋, Oku-Iya Nijū Kazurabashi).
The larger of the two bridges, Husband Bridge (Otto no Hashi), stretches 44 meters across the river next to a small waterfall, while the slightly lower Wife Bridge (Tsuma no Hashi) spans 22 meters just a little ways upstream. The bridges are constructed with steel cables hidden within the vines for safety and are rebuilt every three years. They are connected to each other by a network of paved hiking trails that also lead to camping facilities on the far side of the river.
Another popular attraction is a Wild Monkey Bridge found next to the Wife Bridge. It is a wooden cart suspended on a rope over the river and was used to transport goods and people. Visitors can try out the wild monkey bridge and pull themselves across the river.
A rental car is recommended for visiting the Oku-Iya Kazurabashi Bridges.
Alternatively, take a bus from Awa-Ikeda Station to Kubo (2 hours, 1790 yen, 4 buses/day), transfer to another bus bound for Nijukazurabashi or Mount Tsurugi, and get off at the Nijukazurabashi (二重かずら橋) bus stop (30 minutes, 430 yen, 2 buses/day). Buses from Kubo to the bridge operate only on weekends and during peak seasons from April to November. Peak seasons include Golden Week, the summer holidays (mid July through August) and the autumn color season (October to early November).