Many travel guides will tell you that state of Bihar, in northern India, derives its name from "vihara", the land of monasteries; this is the birthplace of Buddhism, and here is where you'll find the most numerous and significant Buddhist sites in the whole of India.
But Bihar is also the cradle of Indian history. This is where the first empires straddling most of the land mass of the Indian sub-continent arose: Magadha, ruled by the Nandas at the time of Alexander the Great's invasion, and shortly thereafter, the Mauryas, under the great emperor Ashoka, 'one of the greatest monarchs the world has ever seen'. Today's capital city of Patna, on the banks of the Ganges, stands on the ruins of Pataliputra, where the Mauryas built a many-pillared hall of such magnificence that 'even in decay (it) made such an impression on a Chinese traveller (Fa Hsien, in the 5th century) that he thought it the work of spirits'. These were empires that were fabled for their power and their riches; and indeed Bihar boasts the richest agricultural soils in the country.
Yet nowadays Bihar is the poorest state in India, with an (unfortunately so far deserved) reputation for lawlessness. It is mostly shunned by tourists, except for those who shuttle into Bodh Gaya through its recently built international airport, or in the direct train from Benares; thanks to the exploits of Mark Shand and his book "Travels on My Elephant", a few may even have heard of the Sonepur Mela, across the Ganges from Patna (the largest animal fair in India, dwarfing its more glamorous and better-publicised counterpart in Pushkar in Rajasthan; true, no camels here, but nowhere else will you find as many elephants.) And what can compare with the riotous joy of the post-Diwali Chhath Festival, when Biharis fast for a day and a night and flock to the Ganges for puja to the rising sun? Or with the myriad objets d'art in the Jalan collection at Quila House?
I dream that one day tourists will flock into Bihar and discover all its many historical and cultural gems. Indeed I dream someday of being able to take people on a "In the Footsteps of the Buddha" tour in Bihar: to Bodh Gaya, obviously, where the Buddha reached enlightenment; to Rajgir, erstwhile capital of the Magadhan Empire and site of the First Buddhist Council after the death of the Buddha; to Nalanda, site of the largest Buddhist university in the world until its destruction in the 12th century by the invading Muslim armies; and finally to Vaishali, to the stupa where the Buddha's ashes were buried, and to the only Ashoka pillar still standing in situ. Preferably with a cruise on the Ganges thrown in for good measure ...
(All quotes above are from "India: A History", by John Keay. It's a fantastic book that I highly recommend. I read and annotated it thoroughly before my first foray in 2001-2002.)