In this work, the funerary monument to the defenders of Molino del Rey battle erected in 1856 is presented. This is one of the first monuments in the city designed to preserve the memory of the deceased soldiers in the Mexican–American war. The monument conveys the work of the Italian Tangassi brothers who imported to Mexico the monument from Italy, the Carrara marble monument was assembled and placed above the crypt designed by the architect Vicente E. Manero in Mexican volcanic stone. This funerary monument was placed in the battle location in the countryside at the time. Through a systematic diachronic study of the material’s color contrast in the photographs as a visibility marker, it has been possible to determine how the monument transformed materially and how urban development affected its relation to the receivers, modifying the associated collective memory. In the current debate of determining which monuments should be preserved and which not, this paper shows that heritage conservation within urban development needs to consider its multidisciplinary nature in order to sustain policy initiatives to introduce culture as an aspect of sustainable cities development.