In the enthusiasm of the declaration of war against Prussia in July 1870, there was little thought given to the defence of Paris, as it was assumed that the fighting would all be in Germany. In the thirty years since the construction of the wall and the outlying forts, the range of artillery had almost doubled, and there were many vantage points in the hills surrounding the city from which modern guns could dominate the fortifications. During August, work had commenced on a redoubt at Chatillon in an attempt to remedy the most obvious case, but otherwise little was done. However, once news of the French defeats at Spicheren and Wörth reached Paris at the beginning of August, work commenced in earnest.