The site of the square was limited to a medium-effective siege by land and sea since the restorers did not have the men and materials necessary to undertake an assault on the fortress where the Confederate troops were garrisoned. The objective of the besiegers was to exhaust and leave the defenders without provisions to achieve the capitulation of the square. As the besieging army was camped in a marshy and unhealthy area, the casualties due to illness were numerous, which together with the constant departures of the garrison under the command of Colonel de la Guarda made an effective siege difficult. On the other hand, Colonel de la Guarda, whom the Chilean historian
Francisco Antonio Encina describes as energetic, was not content with harassing the besiegers by land and the garrison having been unable to fire their cannons on the Chilean ships due to a direct threat from those of the ships' willingness to open fire on them if their ships were damaged in the firefight. He did not waste any opportunity to attack them with whatever means were within his reach, von Tschudi himself refers to an episode he witnessed while on board the neutral merchant ship
Edmond. The actions at the site were varied, one of them occurred on September 18, when the Peruvian garrison of Callao, provided with enough weapons, bravely attacked the Restoration Army's outposts. The army's troops sustained the attack from 7 a.m., with more than 200 cannon shots being fired from the Real Felipe fortress. Three soldiers from the
Portales battalion, one from the
Carampangue battalion and three wounded from the
Aconcagua battalion were lost. The losses of the besieged forces however, were greater. On October 13, during the night, Second Lieutenant Manuel Antonio Marin was sent to guard the maritime advance, with a picket of 25 soldiers from the
Valparaíso battalion. At dawn the next day, two companies of the besieged forces left their forts, escorting some carts loaded with vessels that were intended to supply the defenders. The restorers, observing this, deployed in guerrillas and broke fire on these companies, the fire being immediately answered by the large infantry and the great artillery pieces of the fortress. The small picket of soldiers from the Valparaíso battalion, despite being at a disadvantage and alternately enveloped by bullets, resisted and managed to force the besieged forces to retreat into their fortresses. The siege was already dragging on for too long, and there were several casualties from the fighting and disease in the area. Adding to the pressure, the annoyances of foreign powers such as
Great Britain,
France and the
United States that prevented an effective blockade and siege of the port. For reasons like these, General Cruz had already told Bulnes the impossibility of completely blocking the castles of the port, pointing out that "it would be better to use [their] forces in a more useful way." After failing all possible negotiations and the besieged not having the intention of capitulating, the Restoration Army lifted the siege, leaving Lima and heading for
Huacho on November 15, before the advance of
Andrés de Santa Cruz's army of 7000 seats and the intent of avoiding a battle at a tactical disadvantage. ==Consequences==