In the course of the Peninsular War, Wellington’s army fought several hard battles and smaller actions, but it was the bloody sieges that troubled him more than anything else. Indeed, the performance of his army during the sieges was probably the most disappointing aspect of what was otherwise an extremely successful campaign. Taking 1808 as its starting point, this title deals with the fortress sieges that involved Wellington’s Anglo-Portuguese army, and concentrates on four key sites in particular (Ciudad Rodrigo, Badajoz, Burgos and San Sebastian). All of these played a vital role in the war due to their strategically important positions. It documents both the sieges and the storming of the fortresses, as well as the general role of the fortresses in Spain and the impact they had on the thinking of the commanders and strategies of the armies involved.