However the existing road system was inadequate to deal with the increased demand; in 1956 only 23% of national highways were paved, which included only two thirds of the main Tokyo-Osaka road (National Route 1).
然而现有的道路系统并不足以应对增长的需求；1956年，仅有23%的日本国道完工，其中包括了东京至大阪的国道1号的三分之二。