Mariano Meseguer Bielsa (Barcelona, Catalonia, Spain, 1927 - 2013) was a Catalan architect and social activist. Son of immigrants arriving from Aragon, Spain. He studied Architecture and then joined the Col·legi Oficial d'Arquitectes of Barcelona. During these years, as a personal quest, he actively investigated and denounced abusive practices in the construction business, to the point that he intervened in both municipal and private projects to protect the local architectural patrimony in Barcelona.
In 1964 he moved to Sarria, Barcelona and got immediately involved with the local association of which he was president during the years of Spain's Transition into Democracy . From that platform he intervened to defend the local artistic and architectural patrimony in various areas in the city. His contribution sealed the preservation of the Jardins de Vil·la Cecília and its tower, where today we find the Casal de Sarria, in Barcelona among others. He was Urban consultant of various neighbor associations, also the Federació d'Associacions de Veïns of Barcelona as well as a member of the Technical Commission for the Review of the Catalogue to Protect the Architectural Patrimony.
In 2005 he was honored the Medal of Honor of Barcelona.[1] In March 2022, the Barcelona city council approved naming two public squares between Salvador Mundi, Mare de Déu de Núria and Hort de la Vila after him and Angelina Trallero, following the proposal by the Associació de Veïns de Sarrià, Barcelona.[2]