Rebels that fight near or capture cities gain more concessions from the government than those that remain in the periphery. Yet, not all groups challenge urban centers. Previous scholarship expects rebel strength to explain this strategic decision. However, weak rebel groups challenge cities, too. Our approach focuses on the conflict process more broadly. We argue that as the network of rebels challenging the government increases, opposition groups become more likely to attack cities as either they become emboldened, given the government’s disadvantage in multi-front wars, or they are propelled to strategic and resource centers in competition with the other groups. Statistical analysis of all African conflicts from 1989-2009 strongly supports this logic, while an exploration of most typical cases highlights each of these mechanisms in practice. This project thus links literature on civil war tactics and conflict contagion.