An observatory is a place set up with a device (or devices) for observing astronomical or meteorological phenomenon, like stars, planets, nebula, etc. Observatories often have powerful telescopes (visual, radio, or other types).
The entire complex of buildings, telescopes, equipment, and staff involving scientific astronomical observations. Small observatories might consist of just one telescope situated in a dome, one instrument and computer, and one observer. McDonald Observatory is an example of a major observatory, and consists of five major telescope in five different domes, numerous instruments, computers, living quarters, outbuildings, astronomers, and engineers.
An observatory is a location used for observing terrestrial and/or celestial events. Astronomy, climatology, geology, meteorology, oceanography and volcanology are examples of disciplines for which observatories have been constructed. Historically, observatories were as simple as containing a sextant (for measuring the distance between stars) or Stonehenge (which has some alignments on astronomical phenomena).