Aioi Tunnel

Aioi Tunnel (相生トンネル) is a railway tunnel on West Japan Railway Company's Sanyo Shinkansen line located between Aioi Station, Hyogo Prefecture and Okayama Station, Kita-ku, Okayama city in Okayama Prefecture with total length of 3,988 m. It was built and completed in 1975. In December 2010, NTT Docomo mobile phone service area covers 14 tunnels on the Sanyo Shinkansen between Himeji and the Okayama prefecture border, including Aioi tunnel.