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The underground are not tunnels but excavated with the road built on top, it's far cheapers than tunnels.
by Kuinox 2y ago
The underground are not tunnels but excavated with the road built on top, it's far cheapers than tunnels.
- SideburnsOfDoom 2y ago> The underground are not tunnels but excavated with the road built on top, Are you describing "Cut and Cover" ? As in "Cut and Cover is a method of construction of shallow tunnels" https://en.wikipedia.org/wiki/Tunnel_construction#Cut-and-cover https://en.wikipedia.org/wiki/Tunnel_construction#Cut-and-co... It has been used for centuries, e.g. was used to dig the first parts of the London underground in the late 1800s