Jaipur is called the pink city because of the color of the buildings, which are lined with sandstone in this color. The most recognizable monument is the Hawal Mahal, i.e. the Palace of the Winds, whose monumental facade allowed the ladies of the court to observe the everyday life of the city. However, I was most impressed by the Jantar Mantar, an astronomical observatory built in the early 18th century by Maharaja Sawai Jai Singh II.