Taj Mahal, the pinnacle of Mughal architecture, was built by the Mughal emperor Shah Jahan (1628-1658), grandson of Akbar the great, in the memory of his queen Arjumand Bano Begum, entitled ‘Mumtaz Mahal’.The mausoleum is located on the right bank of the river Yamuna at a point where it takes a sharp turn and flows eastwards. Originally, the land where the Taj Mahal presently stands belonged to the Kachhwahas of Ajmer (Rajasthan). The land was acquired from them in lieu of four havelis as is testified by a court historian, Abdul Hamid Lahauri, in his work titled the Badshah-Namah and the firmans (royal decrees). For construction, a network of wells was laid along the river line to support the huge mausoleum buildings. Masons, stonecutters, inlayers, carvers, painters, calligraphers, dome-builders and other artisans were requisitioned from the whole of the empire and also from Central Asia and Iran. While bricks for internal constructions were locally prepared, white marble for external use in veneering work was obtained from Makrana in Rajasthan. Semi-precious stones for inlay ornamentation were brought from distant regions of India, Ceylon and Afghanistan. Red sandstone of different tints was requisitioned from the neighbouring quarries of Sikri, Dholpur, etc. It took 17 years for the monument complex to be completed in 1648.
The Taj rises on a high red sandstone base topped by a huge white marble terrace on which rests the famous dome flanked by four tapering minarets. Within the dome lies the jewel inlaid cenotaph of the queen. So exquisite is the workmanship that the Taj has been described as " designed by giants and finished by jewellers".
The only asymmetrical object in the Taj is the casket of the emperor which was built beside the queens, as an afterthought. The emperor was deposed by his son and imprisoned in the Great Red Fort for eight years but was later buried in the Taj. During his imprisonment he was barred from visiting Taj. What he could have was just a little view of Taj in a reflection of a diamond.
The dome is made of white marble, but the tomb is set against an awesome backdrop of the river and it is this background that works its magic of colours through their reflection and transforms the view of the Taj. The colours change at different hours of the day and during different seasons. Like a jewel, the Taj sparkles in moonlight when the semi-precious stones inlaid into the white marble on the main mausoleum catch the glow of the moon. The Taj is pinkish in the morning, milky white in the evening and golden when the moon shines.
.These changes, they say, depict the different moods of woman. Different people have different views of the Taj but it would be enough to say that the Taj has a life of its own that leaps out of marble, provided you understand that it is a monument of love. As an architectural masterpiece, nothing could be added or subtracted from it.
The marble dome that surmounts the tomb is its most spectacular feature. Its height is about the same size as the base of the building, about 35 meters, and is accentuated as it sits on a cylindrical "drum" of about 7 metres high. Because of its shape, the dome is often called an onion dome (also called an amrud or guava dome). The top is decorated with a lotus design, which serves to accentuate its height as well. The shape of the dome is emphasised by four smaller domed chattris (kiosks) placed at its corners. The chattri domes replicate the onion shape of the main dome. Their columned bases open through the roof of the tomb and provide light to the interior. Tall decorative spires (guldastas) extend from edges of base walls, and provide visual emphasis to the height of the dome. The lotus motif is repeated on both the chattris and guldastas. The dome and chattris are topped by a gilded finial, which mixes traditional Persian and Hindu decorative elements.
The main dome is crowned by a gilded spire or finial. The finial, made of gold until the early 1800s, is now made of bronze. The finial provides a clear example of integration of traditional Persian and Hindu decorative elements. The finial is topped by a moon, a typical Islamic motif, whose horns point heavenward. Because of its placement on the main spire, the horns of moon and finial point combine to create a trident shape, reminiscent of traditional Hindu symbols of Shiva.
In all, the Taj Mahal covers an area of 60 bighas, as the terrain gradually sloped from south to north, towards the river, in the form of descending terraces. At the southern point is the forecourt with the main gate in front and tombs of Akbarabadi Begum and Fatehpuri Begum, two other queens of Shah Jahan, on its south-east and south-west corners respectively called Saheli Burj 1 and 2.
On the second terrace is a spacious square garden, with side pavilions. It is divided into four quarters by broad shallow canals of water, with wide walkways and cypress avenues on the sides. The water channels and fountains are fed by overhead water tanks. These four quarters are further divided into the smaller quarters by broad causeways, so that the whole scheme is in a perfect char-bagh.The main tomb of the Taj is basically square with chamfered corners. The minarets here are detached, facing the chamfered angles (corners) of the main tomb on the main plinth. Red sandstone mosque on the western, and Mehman-Khana on the eastern side of the tomb provides aesthetically a clear colour contrast.The Taj has some wonderful specimens of polychrome inlay art both in the interior and exterior on the dados, on cenotaphs and on the marble jhajjhari (jali-screen) around them.
The complex is set around a large 300-meter square charbagh, a Mughal garden. The garden uses raised pathways that divide each of the four quarters of the garden into 16 sunken parterres or flowerbeds.
A raised marble water tank at the center of the garden, halfway between the tomb and gateway, with a reflecting pool on North-South axis reflects the image of the Taj Mahal. Elsewhere, the garden is laid out with avenues of trees and fountains. The raised marble water tank is called al Hawd al-Kawthar, in reference to "Tank of Abundance" promised to Muhammad.The charbagh garden, a design inspired by Persian gardens, was introduced to India by the first Mughal emperor Babur. 
It symbolizes four flowing rivers of Paradise and reflects the gardens of Paradise derived from the Persian paridaeza, meaning 'walled garden'. In mystic Islamic texts of Mughal period, paradise is described as an ideal garden of abundance with four rivers flowing from a central spring or mountain, separating the garden into north, west, south and east.
The exterior decorations of the Taj Mahal are among the finest to be found in Mughal architecture. As the surface area changes, a large pishtaq has more area than a smaller one, and the decorations are refined proportionally.
The decorative elements were created by applying paint or stucco, or by stone inlays or carvings. In line with the Islamic prohibition against the use of anthropomorphic forms, the decorative elements can be grouped into either calligraphy, abstract forms or vegetative motifs.The calligraphy found in Taj Mahal are of florid thuluth script, created by Persian calligrapher Amanat Khan, who signed several of the panels. The calligraphy is made by jasper inlaid in white marble panels, and the work found on the marble cenotaphs in the tomb is extremely detailed and delicate. Higher panels are written slightly larger to reduce the skewing effect when viewing from below. Throughout the complex, passages from the Qur'an are used as decorative elements. Recent scholarship suggests that Amanat Khan chose the passages as well