6. Taj Mahal
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.