Bronco Billy's Pizza operates within the Lyle-Harvey-Dinsmore Building, one of the oldest commercial structures in the Alvarado section of Union City, California, located at 3940 Smith Street in a historic neighborhood that preserves traces of the region's frontier heritage and early commercial development. The building predates the formal incorporation of Union City as a municipal entity, dating back to a period when the region consisted primarily of scattered settlements, agricultural properties, and ranching operations characteristic of early California. The structure exceeds one hundred years in age, representing remarkable continuity with the early commercial development of the East Bay area during the late nineteenth and early twentieth centuries. The architecture reflects the modest commercial construction typical of frontier communities, with solid brick walls, straightforward fenestration, and limited ornamental detail characteristic of utilitarian business structures designed for longevity and practical function. The building's historical significance is evident in its architectural character and its position as a temporal marker of the Alvarado community's commercial development and the early history of Union City's establishment as an urban center. The interior spaces are decorated with historical photographs and artifacts relating to the region's frontier and ranching heritage, including aged images of local cowboys and settlers from more than a century prior. These historical photographs serve as visual documentation of the region's transformation from agricultural landscape to suburban community and the evolution of the local commercial environment. The building's extensive history has resulted in its reputation within paranormal investigation communities as a location of consistent and well-documented supernatural activity, particularly concentrated in the back room and reserved party room spaces where diners gather for private functions and special celebrations. Staff members working during after-hours periods have reported encounters with poltergeist phenomena and unexplained auditory phenomena suggesting paranormal activity within these spaces. Supernatural manifestations have included reports of moving objects within the back room and party spaces, with glasses, bottles, and place settings repositioning themselves without visible human agency or plausible physical explanation. Unexplained sounds and noises occurring without identifiable physical source have been documented in formal and informal accounts by restaurant employees and visiting paranormal researchers conducting investigations. A black figure has been reported by multiple witnesses within these spaces over extended time periods, manifesting as a distinct apparitional presence separate from background shadows or conventional lighting effects. The black figure is described as maintaining a shadowy, nebulous form that appears and disappears with apparent intentionality and purpose. Witnesses report feelings of presence and awareness when the figure materializes. The specific origin and identity of the haunting phenomena remain unknown, though the age of the building and its continuous commercial use throughout numerous decades of local history suggest multiple possible explanations for the reported activity. The building continues to operate as Bronco Billy's Pizza, serving the community as both a restaurant establishment and as an unacknowledged repository of paranormal phenomena that persists across the decades and contributes to the location's cultural significance.