The Philippines is a predominantly Catholic country and religious monumental architecture (RMA) is an integral component of its culture and heritage, both past and present. Little academic attention, however, has been made in understanding concepts and messages being communicated through RMA. In this paper, the Porta Mariae is investigated using the approach pioneered by Lukken and Searle (1993) based on the Paris School semiotics. The Porta Mariae is a concrete structure with a neoclassical design, built to commemorate the tercentenary of Bikolano devotion to Our Lady of Peñafrancia, inspired both by the triumphal arches popular in the Roman Imperial period and by the Catholic tradition of dedicating holy doors to mark important milestones of the Church. While a fairly recent building just a little over a decade old, the Porta Mariae has become a popular landmark and a welcome addition to the cityscape. It is, in fact, among the top places recommended for visitors to Naga City in many travel websites. This study portrays the Porta Mariae as a communication system and reveals subtle messages to pilgrims, devotees, and visitors, that more than meets the eye.