Construction of the mausoleum was essentially completed in 1643 but work continued on other phases of the project for another 10 years. The Taj Mahal complex is believed to have been completed in its entirety in 1653 at a cost estimated at the time to be around 32 million rupees, which in 2015 would be approximately 52.8 billion rupees (US$827 million). The construction project employed some 20,000 artisans under the guidance of a board of architects led by the court architect to the emperor, Ustad Ahmad Lahauri.
The Taj Mahal was designated as a UNESCO World Heritage Site in 1983 for being "the jewel of Muslim art in India and one of the universally admired masterpieces of the world's heritage". Described by Nobel laureate Rabindranath Tagore as "the tear-drop on the cheek of time", it is regarded by many as the best example of Mughal architecture and a symbol of India's rich history. The Taj Mahal attracts 7–8 million visitors a year. In 2007, it was declared a winner of the New7Wonders of the World (2000–2007) initiative.
The Taj Mahal is built on a parcel of land to the south of the walled city of Agra. Shah Jahan presented Maharajah Jai Singh with a large palace in the center of Agra in exchange for the land. An area of roughly three acres was excavated, filled with dirt to reduce seepage, and leveled at 50 metres (160 ft) above riverbank. In the tomb area, wells were dug and filled with stone and rubble to form the footings of the tomb. Instead of lashed bamboo, workmen constructed a colossal brick scaffold that mirrored the tomb. The scaffold was so enormous that foremen estimated it would take years to dismantle.
The Taj Mahal was constructed using materials from all over India and Asia. It is believed over 1,000 elephants were used to transport building materials. The translucent white marble was brought from Makrana, Rajasthan, the jasper from Punjab, jade and crystal from China. The turquoise was from Tibet and the Lapis lazuli from Afghanistan, while the sapphire came from Sri Lanka and the carnelian from Arabia. In all, twenty-eight types of precious and semi-precious stones were inlaid into the white marble.
According to the legend, Shah Jahan decreed that anyone could keep the bricks taken from the scaffold, and thus it was dismantled by peasants overnight. A fifteen kilometer (9.3 mi) tamped-earth ramp was built to transport marble and materials to the construction site and teams of twenty or thirty oxen pulled the blocks on specially constructed wagons. An elaborate post-and-beam pulley system was used to raise the blocks into desired position. Water was drawn from the river by a series of purs, an animal-powered rope and bucket mechanism, into a large storage tank and raised to a large distribution tank. It was passed into three subsidiary tanks, from which it was piped to the complex.
The plinth and tomb took roughly 12 years to complete. The remaining parts of the complex took an additional 10 years and were completed in order of minarets, mosque and jawab, and gateway. Since the complex was built in stages, discrepancies exist in completion dates due to differing opinions on "completion". Construction of the mausoleum itself was essentially completed by 1643 while work continued on the outlying buildings. Estimates of the cost of construction vary due to difficulties in estimating costs across time. The total cost has been estimated to be about 32 million Indian rupees, which is around 52.8 billion Indian rupees ($827 million US) based on 2015 values.
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