The diagrams show the cross-sections of two tunnels, one joining France and Italy and the other joining two Japanese islands.
The figures compare the cross-sections of two tunnels. Figure 1 illustrates a road tunnel joining two European countries, while Figure 2 shows a railway tunnel linking two islands in Japan.
Overall, it is clear that the railway tunnel in Japan is much longer than the tunnel under Mont Blanc. Also, the Seikan Railway Tunnel took much longer to build than the Mont Blanc Road Tunnel.
The depth of the Mont Blanc Tunnel is 3.5 km at its maximum, compared with only 240m for the Seikan Tunnel. However, whereas the length of the Mont Blanc Tunnel connecting Italy and France is only 11.6 km, the Seikan Tunnel is much longer, at 53.85 km.
The construction times of the two tunnels were markedly different. The railway tunnel was built under the sea, connecting two Japanese islands, and its construction took 42 years to complete, starting in 1946 and finishing in 1988. The road tunnel under Mont Blanc, however, was completed in just 8 years, between 1957 and 1965.