It was built in the late 17th and early 18th centuries and was the sixth fortification erected in the city. 

The bastion was used as part of the city's defense system and also served as a prison by the clergy. 

The bastion is dedicated to the first pope, and it was here that the tribunal of the Holy Inquisition was established.  

Its entrance gate features a shield with the papal tiara, the symbol of San Pedro, above the lintel.

Inside, there is a courtyard with a staircase that leads to the upper part, where the sentry boxes can be seen. One of them still preserves its latrine.