San Leucio historical site, a part of UNESCO World Heritage List, is situated in Caserta, Italy, renowned for its distinctive blend of industrial heritage and royal history. Established in the late 18th century by Ferdinand IV of Naples, it was initially used as a royal hunting lodge before evolving into a silk production colony. Among the structures comprising the site, the “Coccoliera” and the “Gran Filanda” were pivotal components of San Leucio silk production complex. This study reports and discusses the comprehensive investigative activities conducted on these two buildings prior to structural analyses. In addition to a historical-critical analysis and geometrical survey of the structures, tests aimed at investigating construction details and mechanical features of existing materials were performed. To these purposes, non-destructive techniques were employed, including: i. Ground Penetration Radar (GPR) tests, ii. Sonic tests, and iii. Resistograph tests. The data acquired and presented in this paper provides the necessary information for further studies aimed at assessing structural and seismic vulnerability of the buildings under investigation.