関門トンネル（門司ー下関） Kanmon Tunnel (Moji to Shimonoseki)

[@user-cf8tj2tu9q]

関門トンネルの中を初めて見ました。とても興味深かったです！

[@StevenTsoi]

Honshu railway Sanyo main line adopts DC supply, while JR Kyushu uses AC supply except the classic line Kanmon Tunnel and Karatsu line. Shimonoseki is within JR West turf, while Moji is a JR Kyushu station. So it is a shuttle service between both stations using dual current rail stock from JR Kyushu. From the beginning of the ride, the train changed its power supply (AC > DC) before entering the tunnel.