The port, fortresses, and monuments of Cartagena were included in the UNESCO World Heritage list in 1984. Nevertheless, since 2017 they are threatened to be categorized as “in Danger” by UNESCO. This research analyzes two main critical aspects, governance and the current state of the site. This study applies an innovative interdisciplinary methodology that merges empirical and scientific approaches to evaluate the governance of Cartagena’s heritage (causes) and its impact on the current state of the tangible cultural heritage (effects). Methodologically, secondary information is used to study governance. The study aims to identify strengths, weaknesses, opportunities, and threats in the UNESCO site governance. Exemplary heritage management systems are studied to propose an adaptable management approach specifically for Cartagena. Over the past five years, qualitative data collected through field observations, along with a photographic report, have revealed significant issues stemming from insufficient heritage management. These problems have rarely been addressed in the existing literature. Furthermore, a quantitative approach was taken by analyzing hyperspectral images obtained from a previous study to identify vegetation and asbestos-cement roofs within the cultural heritage site. It takes a unique perspective by investigating the root causes rather than superficial issues. The study comprehensively analyzes various factors, including material degradation, vehicular traffic, environmental elements, urban structure, and architectural integrity, forming an interconnected framework with governance problems. This research offers a broader perspective that considers complex reality and goes beyond isolated problems and solutions. The study reveals that the ambiguity surrounding decision-making authority for heritage management, distributed between the Mayor’s Office and the Ministry of Culture, is a primary challenge. The lack of coordinated action significantly compromises the conservation and protection of the cultural heritage Site. Moreover, twelve current shortcomings of cultural heritage in Cartagena are identified through the authors’ five-year on-site regular visits, photographic reports, and observation. To address the prevailing concerns, a new line of command for cultural heritage management is proposed as the most effective means of tackling these challenges. Additionally, general recommendations are presented to mitigate the existing problems and prevent the classification of Cartagena’s heritage as “at risk” by UNESCO in the near future. Although, each problem identified would need a research project ad hoc to be fully addressed. This research provides a scientific perspective, drawing upon years of experience studying heritage and residing in the city, devoid of political influences or conflicts of interest.