The Defences
Considerable changes occurred in the defences of Saragossa after the first siege in June-August. In that siege, the city had few fortifications, except for the medieval walls that could not withstand the French artillery bombardment. The defenders consisted of only a handful of regular troops and gunners, plus a mass of thousands of volunteers. They had, however, been able to inflict heavy casualties on the French at the barricades in the narrow winding streets.
Since September 1808, Colonel San Genis had been working on a number of modern fortifications. To the south, the city was protected by the Huerva River, which San Genis used as a moat with two redoubts on the south side of the river: "Our lady of the Pillar" in the south-west corner and the San Jose convent on the south-east corner. These were overlooked by the city walls.
To the west, a solid rampart had been built outside the city walls, incorporating the Augustinian and Trinitarian convents. This provided a central gun battery, as well as a ditch that was 14-metres deep.
San Lazaro was fortified with a rampart protected by waterways and the two convents on the north side of the Ebro River had been made into fortresses.
On the key position of Monte Terrero, San Genis built an entrenched military camp using the Aragon Canal as a moat.
Progress on the fortifications had been slow until the Battle of Tudela. After that it was clear the French could attack at any moment and suddenly 60,000 volunteers were available. If the French had attacked quickly, then even this would not have helped. Due to the delay, however, the Spanish had time to improve the fortifications and obtain sufficient supplies.
Inside the walls, the strong, almost entirely inflammable masonry homes and apartment buildings were laced together with internal passageways, making each block of the city its own barricaded fortress, with the numerous church buildings standing as keeps and strong-points, from which grapeshot and counter-battery fire could command the streets.
The garrison would also be much stronger than in the first siege. Palafox had raised an additional 10-12,000 new recruits in Saragossa plus a further 17,000 survivors of the Battle of Tudela. By the start of the siege Palafox had 32,000 infantry, 2,000 cavalry and 10,000 armed volunteers.
To prevent the danger of magazine explosions, the city manufactured its gunpowder as it was needed.
Supplies of Food and ammunition were sufficient for three months plus private stocks held by townspeople.
Read more about this topic: Siege Of Saragossa