the origins and authenticity of the arch are unclear. the date of construction, set to 1595 (15 years after palladio's death), is certain, like the identity of the patron, the venetian captain giacomo bragadin. there are documented demands of the monks of the sanctuary, dating from 1574-1576, asking the community for financial support for the restoration of the entire path of stairs, but there is no evidence that the arch was included in the general renewal process, which involved the sanctuary itself. at the same way, the original configuration of the arch is uncertain. 17th century images shows the niches in the front of the arch, then moved in the intrados to host the statues of the "annunciation" by orazio marinali.