Tunnels are essential subsurface passages constructed through rock or soil. They provide critical space for transportation (rail and road), utilities (water, sewage, cables), and communication lines in increasingly dense urban environments.
: While construction is expensive—urban tunnels can cost around £50m per km—they are often more economical long-term than aboveground facilities where land is scarce. Tunnel
The concept of a can be explored through multiple lenses: as a marvel of engineering and infrastructure , a powerful literary symbol for personal growth, or a metaphor for hope. 1. Engineering and Infrastructure: Connecting the World Tunnel
