Mountain Lake Park's founder envisioned the town as a destination for recreation, education, cultural enrichment, and religious experiences, so one of its first structures was an auditorium that served as a gathering place for classes, programs, and worship services. Built in the summer of 1882, the first structure resembled a giant car port and, according to the July 1882 minutes of the MLP Association, measured 52 by 80 feet, stood 16 feet high, was supported by white oak columns spaced 10 feet apart, had curtains instead of walls, a small bell hung in a forked oak tree on the south side, three rows of plank seats with back supports, and a ground floor covered with fresh-mowed hay cut on the park grounds. In August 1884, the Association decided to construct at the south end of the auditorium a two-story Assembly House measuring 40 by 80 feet with a bell tower, classrooms, dormitory space, and a gymnasium on the second floor; the minutes specified box-frame windows hung with cords and weights, two coats of good paint, and first-quality materials, with an estimated cost of $3,100, and a contract was signed that September. The following May, the builder was directed to add a 9-foot-wide platform at each end of the building, one likely the porch still on the south front and the other possibly now serving as the stage in the auditorium portion, and the Association also purchased a 500-pound bell for $175. In September of that same year, the sides of the auditorium were ordered boarded up, and in October 1888 the entire structure was officially named the Assembly Hall. Famous visitors to the park who appeared either there or in the Amphitheatre across the street included President William H. Taft, William Jennings Bryan, Mark Twain, and Billy Sunday. The original auditorium section was destroyed by fire in 1941, its replacement collapsed under heavy snow in the 1960s, and the present structure is primarily metal. The property continued in use well into the 1960s as an annual retreat site for the Mountain Lake Park Camp Meeting Association, and after that group disbanded it passed through a couple of owners before coming to the Apostolics of Oakland.