With 2 copies of a strategic resource any City may build any number of units requiring that strategic resource. Most are invisible until revealed by a particular technology.īuilding the appropriate improvement on a strategic resource gives access to 1 copy of that resource. These resources are required to build certain units. This means a city does not act like an improvement on a bonus resource. Bonus resources provide local yield boosts of food, production, or gold when improved.īonus resources may be harvested, which permanently removes the resource in return for 25 times their yield (on Normal speed).įounding a city on a bonus resource does not grant any additional resource yield beyond the resource yield already shown on the tile.