Jantar Mantar

Jantar Mantar is a collection of architectural astronomical instruments used to measure the time of day, correct to half a second. It can also predict eclipses, track stars in their orbits, ascertaining the declinations of planets, and determine the celestial altitudes.

It is listed on the World Heritage List as "an expression of the astronomical skills and cosmological concepts of the court of a scholarly prince at the end of the Mughal period".