The Porta del Soccorso owes its name to the “help” role it played in past centuries in case of emergency: through this hidden passageway, Bergamasks could enter and exit the Walls without being seen.
It was thus possible to catch enemies by surprise, attacking them from an unexpected point, or to flee in case of siege, or even to rush to defend the nearby Castle of San Vigilio.
This was used only in critical situations: in quiet times, neither goods nor people crossed it.
To find it, one has to reach Cavagnis Street and take Via Sotto le mura di Sant’Alessandro.
It is anonymous, with no coats of arms or other distinguishing marks, apart from two vertical slits in the stone that testify to the former presence of a drawbridge; it might look like access to a cellar, when in fact it leads through underground corridors to the square of the Fort of St. Mark.
The square consisted of a space where soldiers, weapons and provisions were housed, and from which several tunnels departed that ended at the gunboats and casemates.
In the event of a siege, the troops would be able to exit through the Porta del Soccorso so as to surprise the enemies and prevent their advance toward the Castle of San Vigilio, the city’s last bastion.
At the same time there was an open-air corridor, which has now disappeared, connecting the fort to the castle.
From here food and ammunition passed through, without the enemy being able to notice it.
After various historical transitions, from the French to the Austrians, St. Mark’s fort is now privately owned, including the Relief Gate and the amazing underground structures.