Bridges, tunnels, roads, roads, conveyors and pipes upgrade

As in Title:
Wooden, concrete and steel bridges.
Wooden, concrete and steel driveways.
Tunnels, a new tunnel boring machine! :)
Conveyors and pipes at an angle would be useful.
Elevators! yes that would be something! And conveyor belts and pipes at right angles.

I've thought of this as well... a bridge spanning over your coal/ore mine would be great, esp. in New Haven where reaching the gold is surrounded by coal, ore, and copper ore, making a bridge to it would be amazing.