Initially the Hill Observatory had two domes, and two other buildings which are now houses. A third dome was added in the 1930s. When the Society began to use the site the residential buildings had been sold and little more than the domes remained, affording a floor area then of 90 square metres. Due mainly to the efforts of the Society, the floor area now in use is around 390 square metres, enabling us not only to do more astronomy, meteorology and radio work, but to present these to the visiting public.