Officials said after puja is performed by Hindu seers, the survey for the hidden gold begins at 11 a.m. at the old fort at Dondia Khera village. The fort belonged to Unnao's mid-19th century ruler Raja Rao Ram Bux Singh. Unnao is 50 km from the state capital Lucknow.
ASI officials have been camping at the site for the last three days and have completed marking the area of the potential treasure trove late Thursday amid tight security.
Thousands turned up at the site as the news spread of the venerated seer, Shobhan Sarkar, having dreamt of the fort's hidden treasure trove. The district administration has now banned the entry of people into the fort premises.
Shobhan Sarkar, a famous seer of the region, wrote to the prime minister a few weeks back, that the late king came in his dreams and asked him to get the treasure dug up and hand it over to the government of India to tide over the economic crisis.
His devotee, Congress leader Bhakt Charan Das also visited the saint and then urged the ASI to take up the issue.
Preliminary findings, officials say, have suggested presence of "some metal underneath the earth", following which ASI teams decided to begin the excavation.
Experts, however, are not too sure about the possibility of gold buried underneath.
While many do not rule out the discovery of some gold, they say it is not possible for 1,000 tonnes of gold to have been buried within the fort as Raja Rao Ram Bux Singh was a ruler who presided over a zamindari stretching not more than 25-30 km.
"He was not a big king and hence it looks unlikely that such a huge gold reserve would be found there," said D.P. Tiwari, former head of the History and Archaeology department at the Lucknow University.
For the villagers, however, Shobhan Sarkar's words are sacrosanct.
Mahendra Pratap Singh, a descendant of the late Unnao ruler, says people firmly believe that if the seer has said it, the gold must be somewhere there.
People have also demanded that if the hidden gold is indeed found, 20 percent of it be spent on development of the area.
Raja Rao Ram Bux Singh fought the British forces along with Rani Laxmibai of Jhansi during the 1857 First War of Independence and was overthrown in the process. He went into hiding, but was captured by British forces in Varanasi and sent to the gallows.