Civilization manualBook 1: From Bare Hands to Steam and Electricity765 entries · 23 phases · 100 years
The Island
Phase 19 — Roads, bridges, flyovers and tall buildings  /  About year 58
19.08

Cofferdam and caisson ⚠

a dry place to work under water, for the piers of bridges and the walls of harbours

MakingYear 58Stands on 239 earlier

AWhat it needs

Needs 239 other products in all, 3 of them directly.

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