Leiden Observatory

Leiden Observatory (Dutch: Sterrewacht Leiden) is an astronomical institute of Leiden University, in the Netherlands. Established in 1633 to house the quadrant of Rudolph Snellius, it is the oldest operating university observatory in the world, with the only older still existing observatory being the Vatican Observatory.

The observatory was initially located on the university building in the centre of Leiden before a new observatory building and dome were constructed in the university's botanical garden in 1860. It remained there until 1974 when the department moved to the science campus north-west of the city. Notable astronomers that have worked or directed the observatory include Willem de Sitter, Ejnar Hertzsprung and Jan Oort.