The Taj Mahal, ('Crown of the Palace'), is an ivory-white marble mausoleum on the southern bank of the river Yamuna in the Indian city of Agra. It was commissioned in 1632 by the Mughal emperor Shah Jahan to house the tomb of his favorite wife, Mumtaz Mahal; it also houses the tomb of Shah Jahan himself. The tomb is the centerpiece of the complex, which includes a mosque and a guest house, and is set in formal gardens bounded on three sides by a crenellated wall.

The Yamuna River is the longest tributary in India, 855 miles (1,376 km), and the second-largest tributary of the Ganges River. It rises on the slopes of the Bandarpunch massif in the Himalayas and flows in southerly direction swiftly through the foothills. The river then passes Delhi, where it feeds the Agra Canal. South of Delhi it turns southeastward and passes Agra and the Taj Mahal. The Yamuna eventually confluences with the Ganges River.

The name Yamuna is derived from the Sanskrit word "yama", meaning 'twin', and it may have been applied to the river because it runs parallel to the Ganges.

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