“In a foreign country one is obliged to see everything” Mérimée as “witness” to an execution (Lettres d’Espagne), actual topography and possible models

Did Mérimée really see the execution described in the Lettres d’Espagne? Critics have so far neglected the question of the topographical verisimilitude of the various v antage points adopted by the narrator, and one possible model: the torture of Damiens described by Casanova, which Mérimée may have come across in one of the many versions published at the time. But in the context of the Romantic travelogue, do these questions help determine the authenticity of the story?