Taj Mahal is a colossal mausoleum built of white marble stone. It was built in Agra between 1631 and 1648 under the Mughal emperor Shah Jahan in memory of his favourite wife, Mumtaz Mahal. The Taj Mahal is the jewel of Muslim art in India and is one of the most universally admired masterpieces in the world and is once of the most visited tourist spots on earth.

Here are a few amazing facts about Taj Mahal:

• Shah Jahan, the Mughal emperor who ordered the construction of Taj Mahal, spent nearly 32 million rupees on its construction. This was many years ago, today the amount would be close to $1 Billion.
• The architecture of Taj Mahal has many influences namely British, French, Mughal, Arabic and Hindu. The palace contains 120 rooms.
• Today, Taj Mahal is chosen as one of the new Seven Wonders of the World.
• About 28 different types of precious and semi-precious stones were used for adorning the Taj Mahal. They were sourced from  various parts of the world such as Sri Lanka, China, Tibet and some parts of India.
• If you observe carefully, you can notice that the four minarets of the Taj Mahal are tilted outwards and they do not stand straight. The main reason for this is to protect the tomb from being damaged with the falling of minarets on it due to a natural calamity like an earthquakes, floods etc.
• It is saidd that Taj Mahal's garden included abundant flowers such as daffodils, roses and fruit trees. It was by the end of the 19th Century the British empire took the control and they changed the landscaping according to their liking which resembled the lawns of London.
• Earlier, Taj Mahal was to supposed to be built in Burhanpur where Mumtaz died during the childbirth due to postpartum hemorrhage. But unfortunately, Burhanpur couldn not supply enough white marble and so the decision was taken to build the Taj Mahal in Agra.
• Shah Jahan’s other wives and some servants are buried in the mausoleums that are present outside the Taj Mahal.
• Taj Mahal is one of the most visited and beautiful monuments in India, it has over 4-8 million visitors every year. Sometimes there are about 40-50 thousand visitors on a single day.
•  It took almost upto 22 years to build the Taj Mahal! Several small refinements were made later on.
• Over 20,000 labourers were involved in the construction of this colossal project.
•  It is actually forbidden for any aircraft to fly over the Taj Mahal. It is a no-fly zone.
• It is said that The Taj Mahal is visible from the Jasmine Tower of Agra Fort .
• There are stories that claim that the arms of the artisans who worked on the Taj Mahal were cut-off  and their eye-balls guaged to make sure that no such monument was ever built again. But this is a hoax. 
• There are replicas of The Taj Mahal that were built in Dubai and Bangladesh.
• Mumtaz Mahal was in labor for 30 hours before she died at age 40.
• Ustad Ahmad Lahauri, regarded as the chief architect of the Taj Mahal, was Persian from Iran.
• Over 1,000 elephants were used to in the contruction of the Taj Mahal to transport heavy materials and supplies for construction.
• Shah Jahan was actually put under house arrest by his own son, Aurangzeb. 
• The Taj Mahal's white marble is turning yellow because of terrible air pollution in Agra. Only electric vehicles are allowed near the structure . Visitors must walk or take electric buses from the parking area to the site of the Taj Mahal.
• The Taj Mahal is cracking at an alarming rate due to lack of groundwater beneath the structure. Wooden foundations made of timber — once submerged — are thought to be rotting at a faster rate too. The minarets are also beginning to lean more.
• The ceiling of the main hall of the Taj Mahal contains a small hole which is perpendicularly right above Mumtaz Mahal’s tombstone.
• The Taj Mahal is taller than the Qutub Minar. The Taj Mahal surpasses the Qutub Minar by about 5 feet.
• It is a myth that the Taj Mahal was supposed to have a black twin and was supposed to be the mirror image of this Taj.
• The Taj can change colors! The colour of the Taj Mahal differs as per the time of the day and the condition of the sky. It gives out a pink hue during the early morning hours. During the evening , the Taj Mahal looks milky white. In the night, under the moonlight, the Taj Mahal gives out a light blue hue. This is very fascinating to see.
• The architecture of the Taj Mahal is a combination of Islamic, Indian as well as Persian style.