The project aims to create an AR mobile application about Fort Santiago. This mobile application features the 3D models of the past and present versions of different historical landmarks within Fort Santiago using augmented reality. This also includes 2D map of the location of the historical landmarks as well as audio narration and 3D animation. A promotional website with content management system was also developed to promote the application to the public. To prove that the application is working, the researcher conducted a survey with a total of 61 respondents, consisting of 41 Visitors/Tourists, 5 Intramuros Administrations Staff and Employees, and 15 IT Experts. Based on the results of the survey, the research was deemed to improve its overall capabilities, features, and performance according to the feedbacks provided by the respondents. There were also recommendations for adding notification features for future events related to Fort Santiago and adding gridlines for augmented reality to aid users in precisely scanning landmarks. In addition, adding more featured landmarks and interactable figures could enhance the experience and interactivity of the application as well as the engagement of visitors within Fort Santiago.