In recent years, video games have emerged as a significant medium for historical and cultural representation. Los Alamos, the core site of the Manhattan Project during World War II, holds immense historical and cultural value both in the United States and globally. Based on oral history sources, this study presents the design and development process of “The Hill,” a historical video game based on the cultural heritage of Los Alamos and explores in detail the role of video games in the digitization, dissemination and educational applications of historical heritage. The development process encompasses historical data extraction, game design documentation, narrative reconstruction, quest structuring, 3D environment reconstruction, Unity development, and playtesting. The findings highlight the intricate trade-offs between free exploration and content guidance, as well as between gameplay and historical education in heritage-based 3D video games. The study suggests dynamically balancing historical authenticity, entertainment, and educational value within the constraints of historical accuracy in both narrative design and 3D environment reconstruction. Beyond documenting the innovative practices employed in The Hill, this research explores the potential and limitations of historical game design in interactive storytelling and player-driven historical experiences. The insights derived contribute to the theoretical and practical development of heritage-based video games and digital history education, expanding the possibilities for video games as a medium for historical dissemination.