Hazare left the jail and is walking part of the way to a memorial to Mahatma Gandhi.
Anna Hazare raises slogans after walking out of Tihar Jail on August 19.
One group offered prayers to the gods, others chanted "the whole country is Anna".
Anna Hazare, who has become a symbol of popular outrage over endemic corruption in India was due to leave Tihar jail on Friday to carry on his fast after a beleaguered government caved in to huge protests across the country.
A large number of people turned up at the jail to welcome the anti-corruption crusader's release.
Several Twitter accounts have been set up by supporters to send out messages of where and when to protest.
A medical team is on standby to monitor Hazare's health as he began his hunger strike in jail and a sharp deterioration could further worsen the crisis for the government, although his supporters say it is not a fast-to-death.
Hazare, a long-time social activist who is often compared to independence leader Mahatma Gandhi, became the unlikely thorn in the side of the ruling coalition when he went on hunger strike in April.
Prime Minister Manmohan Singh, 78, who is widely criticised as out of touch, dismissed the fast by Hazare as "totally misconceived" and undermining the parliamentary democracy.
A weak political opposition means that the government should still survive the crisis, but it could further dim the prospect for economic reforms and hurt the Congress party in key state polls in 2012 that will pave the way for a general election in 2014.
Students, lawyers, teachers, executives and civil servants have taken to streets in cities and remote villages stretching to the southern end of the country.
In the financial capital, Mumbai, the city's iconic lunch carriers, known as Dabbawallas, were reportedly set to go on strike in sympathy with Hazare.
The protests across cities in India, helped spread by social networks, have not only rocked the ruling Congress party, they have sent shockwaves through the political class.
One Facebook fan page for Hazare has 285,000 followers, while the India Against Corruption page on Facebook has more than 350,000 followers where links and messages of support are posted.
The Delhi Police had offered 21 days and later the two sides agreed on 15 days but that can be reviewed and the protest can be prolonged depending on what the government does on the demands put forward by Hazare.
He called off that fast after the government promised to introduce a bill creating an anti-corruption ombudsman.
The so-called Lokpal legislation was presented in early August, but activists slammed the draft version as toothless because the prime minister and judges were exempt from probes.
A fumbling official response has seen the Congress party-led government face one of the most serious protest movements since the 1970s, just the latest setback for Prime Minister Manmohan Singh's second term that has paralysed policy making and economic reforms.
[caption id="attachment_802831"] Hazare, who began his fast on August 16, has been demanding acceptance by the government of the Janlokpal Bill that would bring within its ambit the Prime Minister, higher judiciary and the conduct of MPs within Parliament besides other provisions.[/caption]
Hazare will take a car to open Ramlila grounds in central Delhi, where supporters were making final preparations for his fast.
The crowds had swelled from the time of his arrest.
Crowds have not moved an inch from his side.
The whole country seems united on this front and the government seems to be bowing out.
Over the time in Tihar, the support of the people never wavered for even a second.
Anna seems to have successfully touched a chord with all people.
In celebrations and cheers and patriotic sloganeering, Anna Hazare came out of Tihar to address the supporters.
He has people from all over the country rooting for his success in this hunger strike.
Hazare, who had been arrested earlier in the week and then ordered released, had refused to leave jail until he was allowed to fast publicly.
Being called the new Gandhi og India, Hazare seems to be carrying a huge responsibility on his shoulders.
Traffic was thrown out of gear by the mass procession.
Anna Hazare took a slight detour on his way to the Ramlila Maidan.
Protests are simultaneously being staged all across thew country as Anna fasts on.
Supporters expressed happiness over the 73-year-old activist's decision to come out from the prison complex following rounds of negotiations with the police and authorities to decide on agitation venue to undertake hunger strike.
Anna Hazare's peaceful protest seems to have garnered massive supports from all over.
This is the first time in 120 years that the Dabbawalas have not worked.
Anti-corruption crusader Anna Hazare waves to the crowd after emerging from the gates of Tihar Jail where he was lodged since August 16.
Rains did not deter Anna or his supporters.
Anna Hazare, 73-year old Gandhian came out of Tihar jail on August 19 and made a brief address to the waiting supporters.
It seems that the fight has restarted with Anna's release.
He addressed the crowds at the Ramlila Maidan.
He stopped at Rajghat and said his prayers.
Though release orders for Hazare were issued soon after he reached Tihar, the Gandhian refused to come out unless allowed to hold his fast unconditionally.
Dabbawalas in Mumbai called a strike to participate in the protests.
Outside the jail, hundreds of Hazare's supporters waved India's national flag and danced to music as they waited his appearance.
Lauding the role of the youth in the anti-corruption agitation, Hazare said revolutions all over the world were spearheaded by the youth.
As the news goes, there are 36 doctors on call for Hazare.
The doctor's examined him and declared him fit for the hunger strike.
The rain and the crowds have brought Delhi to a stand still.
The second freedom struggle has started from August 16; said Hazare while addressing supporters outside Tihar.
Amidst heavy security, he made his way to the Ramlila Maidan.
[caption id="attachment_802863"] Anna Hazare addressed the people of his village from Tihar jail in Delhi over phone and assured that he was in good health. He also addressed the crowd outside Tihar.[/caption]
After three days in jail, the government has allowed Anna Hazare to stage a 15-day hunger strike.
Hazare's associate Kiran Bedi told reporters that he will go in a procession from the jail to Mayapuri, distance of about four-five kms and then drive down to Rajghat. From there he will go to India Gate in central Delhi before moving to Ramlila Grounds, a short distance from there.
Government has said that 34 of 40 principles of Team Hazare had been accepted by it during talks for drafting the Lokpal bill, but added that insistence of the team that only their version of bill should prevail was not reasonable.