The bastion was the first to be completed and was named after Santa Rosa de Lima.

To this day, you can still see a monogram of the Virgin Mary on the lintel of its door. 

It has a pentagonal floor plan with a small interior courtyard. 

On its upper part, three sentry boxes can be seen, which were part of the lookout post.

Currently, it houses the Campeche painting gallery, where works by local artists are exhibited.