a fragment of the world's largest ancient sundial.

architecture landmark steeple history fragment largest ancient sundial world's base orange sandstone curved measuring surface marble blue sky india jaipur jantar mantar observatory sundial observatory jaipur unesco mantar largest brihat samrat yantra astrological large measure extraordinary clock steps unique sun dial curve scale instrument india sandstone measurement staircase observation calculation geometric shapes astronomical historical instruments heritage astronomy marble sky jantar astrology famous structure time indian history blue stone historic ancient landmark old