Iya Valley Toll Road

…There is a gravelly schist near the sightseeing boat landing point, which is designated as a prefectural natural monument. In 1964, the area was designated as Tsurugi-san Quasi-National Park, and in 1974, the prefectural Iya Valley Toll Road was opened, connecting Oboke with the Iya Valley to the east in the shortest distance, so Oboke Station came to serve as a base for tourists in the Iya region. Both the JR line and National Route 32 are difficult areas where repair work is often done. …

*Some of the terms mentioned in relation to the Iya Valley Toll Road are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…遊覧船発着場付近にレキ質片岩があり，県の天然記念物に指定されている。64年剣山国定公園に指定され，74年大歩危と東の祖谷（いや）渓を最短距離で結ぶ県営祖谷渓有料道路が開通したため，大歩危駅は祖谷地方への観光基地としての役割をもつようになった。JR線も国道32号線も補修工事の多い難所でもある。…

※「祖谷渓有料道路」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報