Illuminatiscott
Chieftain
They could take dozens or scores of turns to build, but absolutely change the world when they were completed. cases in point? panama canal, chunnel, hoover dam, etc. I think they are vital to earth, and should be vital to a civilization game as well. Canals and bridges could be crossable to both naval and land units. Dams could create water tiles upriver, and provide better ground (such as turning plains into grassland upriver, or swamp/jungle into grassland/forest downriver). these units' owners could charge a fee for them to be used by other nations. there could even be collaborative efforts and neutral ownership. comments?