The Immersive Archive is an initiative dedicated to preserve and restore the groundbreaking works from across Extended Reality (XR) history. Originating at the University of Southern California's Mobile and Environmental Media Lab, this archive is committed to developing and exhibiting simulations of influential XR devices that have shaped immersive media over time. This paper examines the challenges and strategies involved in archiving seminal XR technologies, with a focus on Morton Heilig's Sensorama and Ivan Sutherland's HeadMounted Display. As pioneering prototypes in virtual and augmented reality, these devices provide valuable insights into the evolution of immersive media, highlighting both technological innovation and sensory experimentation. Through collaborative archival efforts with institutions such as the HMH Moving Image Archive at University of Southern California and the Computer History Museum, this research integrates media archaeology with digital preservation techniques. Emphasis is placed on documentation practices, restoration of physical artifacts and developing simulations of these historic experiences for contemporary virtual reality platforms. Our interdisciplinary approach to archival methodologies, which captures the multisensory and interactive qualities of these pioneering devices, has been instrumental in developing a framework for future immersive media preservation initiatives. By preserving the immersive essence of these early experiences, we lay the groundwork for future generations to explore and learn from the origins of immersive media. Safeguarding this rich legacy is essential to ensure these visionary works continue to inspire and shape the future of media landscapes.