Perched atop the Kaimur Hills, an extension of the Vindhya Range, at an elevation of 280 feet (85 m) above sea level, the Chunar Fort, also known as Chandrakanta Chunargarh and Charanadri, is located on the rocky bank of River Ganges, at a distance of 35 km from Mirzapur and 40 km from Varanasi, in Uttar Pradesh. Built in a commanding position, high above a bend in the Ganges, the approach to Chunar Hill is marked by a chain of low hills, running parallel to the river on its right bank, which rises abruptly from the plain, and encroaches into the river for some distance. Although the archaeological records traces its settlement to the 5th-6th century BC and the recorded history of the fort emerges during the time of the Mughal Emperor Babar, the origin of the city goes back to the pre-historic era of legends and myths. According to a legend, to curb the pride of King Bali, a powerful demon king who had taken control of the three worlds, Lord Vishnu, in his incarnation as a Vamana or a dwarf, appeared before him as a small structured Brahmin and begged a piece of land for his three feet. When the king agreed, the little Brahmin grew in size, placed his first feet on a hill, and the second feet in between Earth and heaven. As there was no more space to place the third foot of the Brahmin, King Bali to keep his promise, lowered his head and with his third foot, Vishnu pushed him down, banishing him forever in the Pataal Loka, the Netherworld or the Underworld, the subterranean realms located beneath the Earth. Nevertheless, as Lord Vishnu placed his first step on the hill, it was renamed Charandari, which was later shortened to Chunar.

According to another legend, Maharaja Vikramaditya, the King of Ujjain, built the fort for his brother Raja Bhartihari. But another version of the story says, King Vikramaditya only built a shelter at the location, for his brother, Bharatthari or Baba Bharthari, a follower of Goraknath, who opted to live the life of a hermit, and started living near the rock face of Chunar. However, according to Alha-Khand, a long heroic poem, written by Jagnayak or Jagnik, King Sahadeo made the Chunar Fort as his capital, renamed it as Nainagarh in 1029 AD, and also built a stone umbrella with 52 pillars to commemorate his victory over 52 other kings. Nevertheless, Chunar first came into prominence in 1177 AD, when Prithviraj Chauhan, a king in Rajasthan brought the settlement under his rule, along with several other neighbouring villages, and said to build the fort, which later came under the rule of the Mughal ruler Babar in 1525 AD. But within a short time, Sher Khan, later known as Sher Shah Suri, a highly ambitious Pathan of Afghan descent, captured the fort in 1532, with the intention of becoming the Sultan in Delhi. But his ambition was never fulfilled, and he died in 1545. After the death of Adil Shah, the last ruler of the Suri dynasty in 1557, the fort was recaptured by the Mughal Emperor Akbar in 1575, and then it passed to the Nawabs of Awadh in the 18th century. Finally, the Chunar Fort was captured by the British in 1791, and was used by them as a jail for the prisoners, as well as a warehouse to store weapons.

Built and rebuilt several times by the different rulers of different ages, the architecture of the Chunar Fort displays a unique blend of different styles and cultures. Unfortunately, a large section of the fort is now under the Uttar Pradesh Police, who runs a training school within the premises, leaving only a small area containing several buildings like the Diwan-e-Aam or the House of Commons, complete with an ornate oriole window, and other structures, accessible to tourists. Apart from that, the other notable structures located in the campus of the Chunar Fort include the Sonwa Mandap, The dargah or the tomb of Saint Shah Qasim Sulaimani, the Hanging Place, The Well of Love, the underground prisons, and the bungalow of Warren Hastings, which is out of reach of the tourists.

Constructed in the Hindu style of architecture, the Sonwa Mandap, an open air pavilion with 28 pillars, is equipped with four gates and a tunnel in its front yard. Sandeva, the King of Nepal, constructed the pavilion in 1333, for his daughter, the beautiful princess Sonwa with golden hair, who frequented the place to take her bath in the Ganges, through the tunnel. There is also a bawdi, or a step well, a well accessed by descending a set of steps, measuring 17 feet (5.2 m) in diameter and of nearly 200 feet (61 m) in depth, connected to the River Ganges, and containing perennial water. There is a temple, dedicated to Saint Bhartri Nath, located at the back of the Sonwa Mandap, where regular religious ceremonies are conducted. It is said that the Mughal Emperor Aurangzeb ordered to demolish the temple, but could not destroy the image of the deity, due to continuous attacks by a swarm of bees, and finally, had to give up the process of destruction.

The fort has a well in its complex, around 15 feet (4.6 m) in diameter and known as the Well of Love, which is said to be built by King Vikramaditya for the use his loving wife, where she used to take baths, attached to several underground changing rooms. At the same time, there is also the Well of Death, where the prisoners were once thrown to meet their end, and the hanging house, where prisoners were hung, followed by throwing the bodies in the river.

The rectangle shaped building, constructed in 1753, and located on the top of a small hill, offering beautiful sight of the flowing Ganges, was later occupied by Warren Hasting. The building, equipped with a high ceiling, thick walls and a tiled sloping roof, is devoid of any ornamental decoration. However, the high ceiling contains several small vents that allow seepage of light and air from outside, which keep the inner space cool during the hot summers. There is a Sun Dial within the periphery of the building, built in 1784, and also the umbrella with 52 pillars, built by King Sahadeo, commemorating his victory over 52 other kings. The building has since been converted into a PWD Rest House for Government officials, and out of the reach of the commoners. Interestingly, located adjacent to the Rest House, there is a building with a majestic seat in a balcony, locally known as Jharokha, where Fatima Begum, the Queen of Sher Shah Suri, once used to take her seat and view the royal sessions.

Unfortunately, Chunar Fort is now almost an army cantonment, and hardly 10% of the fort is open for the public. However, apart from the allowed free zone, visitors can also enjoy the panoramic views of the Ganges River from the fort's ramparts, without any restrictions. In addition, interested persons may also visit the domed and unadorned tomb of Saint Shah Qasim Sulaimani, a saint of great fame during the reigns of Akbar and Jahangir, elevated on a broad terrace with sandstone screen carvings, which is located outside the fort compound, about half a mile south-west of the fort.