Bordeaux Observatory, Astronomical observatory in Floirac, France.

Bordeaux Observatory sits on elevated ground overlooking the Garonne River with multiple scientific buildings spread across its grounds. The site brings together observation instruments, laboratory spaces, and administrative areas designed for conducting astronomical research.

The facility began operating in 1878 under the direction of Georges Rayet with a focus on systematic astronomical observations of the sky. It was established as a modern research center dedicated to gathering scientific data and advancing knowledge of the heavens.

The observatory keeps a library holding complete works by Copernicus, Galileo and Newton, alongside instruments and archives from more than a century of activity. Its founding director Georges Rayet published the first volume of the Annales de l'Observatoire de Bordeaux in 1885. The site is inscribed as a monument historique since 2 April 2010.

The observatory stands on a hill above the Garonne in Floirac, and the staff left these buildings in 2016 for a new site at the University of Bordeaux in Pessac, so the historic instruments and library are no longer in active daily use. Check with the Observatoire aquitain des sciences de l'univers before planning a stop.

The observatory's library holds complete works by Copernicus, Galileo and Newton. Its 38 cm equatorial refractor, ordered in 1878, had a Merz lens and a mounting finished in 1881 by Paul Gautier. Between 1983 and 1988 its automatic meridian circle supported the Hipparcos space mission.