JR Central, which operates the Japanese high-speed "Tokaido Shinkansen", also operates 12 conventional lines totaling 1,420km. To ensure stable operation, state-of-the-art equipment is used for maintenance, such as the line inspection vehicle "Dr. Tokai", which inspects tracks down to 0.1mm using a two-dimensional laser. Discover how conventional lines are maintained, then meet the specialists who detect deterioration of iron bridges by making full use of their experience and their 5 senses.