Jantar Mantar, the Pink city's celebrated astronomical observatory built in early 18th century, has been granted World Heritage status by Unesco.
The decision was taken in Unesco's World Heritage Committee meeting in Brasilia.
"This is India's 28th and Rajasthan's second site (after Keoladev National Park) which has been given this status and it is a matter of proud for us and for nation as well," state tourism minister, Ms Bina Kak, told reporters here.
The ancient observatory, built by the Maharaja Jai Singh II at his then new capital of Jaipur between 1727 and 1734, was among the seven sites in the world which have been added to Unesco's World Heritage list this year.
"I received a phone call in the wee hours of today from state Principal Secretary-Tourism, Ms Usha Sharma, from Brasilia that Unesco has given 'Jantar-Mantar' the status of World Heritage site," Ms Kak said.
She said a three-member team of representative from the state presented a management plan before the Unesco committee yesterday following which Jantar-Mantar was declared a World Heritage site.
The committee discussed over 37 sites across the world in the meeting at Brasilia.
"We were making efforts for the past one year to get it the prestigious status, and submitted a management plan as asked by the Unesco committee," she added.
Ms Kak said the status would boost tourism sector in the state and in Jaipur, particularly.
"Hotel industry will get benefits following the status. The state government would also consider over concessions which can be offered to the industry. We expect that tourists inflow which is around 8 lakh would increase during the upcoming tourists'season," she said.
The Maharaja had built a total of five such facilities at different locations, including the ones at Delhi and Jaipur. However, the Jaipur observatory is the largest of these. Ujjain, Mathura and Varansi have also these 'Calculation Instrument' of ancient India.
The observatory has religious significance and ancient Indian astronomers used it to understand the celestial phenomenon.
It consists of fourteen major geometric devices for measuring time, predicting eclipses, tracking stars' location as the earth orbits around the sun, ascertaining the declinations of planets, and determining the celestial altitudes and related ephemerids.