English Heritage staff conducting a photogrammetric survey of the exterior of Windsor Castle. Documentation can provide a lasting record of cultural heritage—essential for conservation or recovery from an unforeseen catastrophic loss. When a disastrous fire in 1992 destroyed much of Windsor's St. George's Hall and Grand Reception Room, English Heritage was able to use photographic documentation taken years earlier, as well as new material, to guide restoration work. Photo: Courtesy of English Heritage, with acknowledgment of the Royal Household at Windsor Castle.