The young and old, men and women, some with children, collected outside the gates of the BJP headquarters, anxious for a last glimpse of the late leader before the state funeral at the Rashtriya Smriti Sthal on the banks of the Yamuna later in the day.
Some clambered on a neem tree outside the BJP headquarters for a better look, desperate to be part of the proceedings but unable to get inside.
Two big LED screens were placed outside the office.
Inside, Prime Minister Narendra Modi, BJP president Amit Shah and a host of ministers and party workers paid their last respects to the late leader, mourned by them and the opposition as one of India's tallest leaders.
The air was solemn as Vajpayee's body, draped in the tricolour, was placed on a platform draped in white flowers. Hundreds of people filed past the body in silence, with a large portrait of a smiling Vajpayee -- a BJP flag on either side -- in the backdrop.
Bhutanese King Jigme Khesar Namgyel Wangchuck and Bangladesh Foreign Minister Abul Hassan Mahmood Ali were among the foreign dignitaries who arrived here to pay their last respects to the former prime minister.
Sri Lanka's Acting Foreign Minister Lakshman Kiriella, Nepal's Foreign Minister Pradeep Gyawali, Pakistan's acting information minister Syed Zafar Ali and a senior minister from Afghanistan are also expected to arrive later in the day, official sources said.
Opposition leaders like CPI's D Raja and CPI(M)'s Sitaram Yechury were among those who visited the BJP headquarters to pay their respects.
Earlier in the morning, hundreds of people chanted "Atal Bihari Amar Rahe" as Vajpayee's cortege made its way from his home through the city to reach the BJP office.
Mourners walked and ran beside the carriage, also chanting slogans like 'Jab tak sooraj chand rahega Atal ji ka naam rahega", punctuated by patriotic cheers of 'Bharat Mata ki Jai' and 'Vande Mataram'.
A decorated gun carriage carrying his mortal remains had left his home on Krishna Menon Marg around 10 am and reached the party's headquarters at Deen Dayal Upadhyay Marg, about five kilometres away, around 11 am.
In the crowd were Ganeshan, 38, and Chennaiah Nadesan, 45, who had flown in from Tamil Nadu.
"This massive turnout of people who have come here to pay their respects to Atalji shows that he resided in the hearts of people. Not only has India has lost a leader, a son, the world has lost a statesman," BJP leader Anurag Thakur told reporters.
The funeral procession will go through Bahadur Shah Zafar Marg, Delhi Gate, Netaji Subhash Marg, Nishadraj Marg and Shanti van before reaching Smriti Sthal, Delhi Traffic Police said in a tweet.
Police has made elaborate security arrangements for the funeral procession, officials said.
Seen as a moderate face of BJP, Vajpayee first became prime minister in 1996, leading a shaky coalition whose members were suspicious of the BJP's right-wing politics. It lasted for 13 days and collapsed after losing a vote of no-confidence.
His second stint as prime minister was in 1998 when the National
Democratic Alliance again came to power but that lasted for just 13 months.
Finally, the NDA with Vajpayee as PM returned to power in 1999 and was voted out in 2004.
In the morning, Congress President Rahul Gandhi, Andhra Pradesh Chief Minister N Chandrababu Naidu, National
Security Advisor Ajit Doval, Army Chief Bipin Rawat, Chief of Naval Staff Admiral Sunil Lanba and RSS chief Mohan Bhagwat paid homage to the former prime minister at his official residence.
In view of the funeral procession, several roads in the national
capital have been closed for the public later in the day.
Some roads closed from 8 am include Krishna Menon Marg, Sunehri Bagh Road, Tughlak Road,Akbar Road,Tees January Marg, Man Singh Road,Bhagwan Dass Road, Shahjahan Road andSikandara Road.
DDU Marg,IP Marg,BSZ Marg (from Tilak Bridge to Delhi Gate),JLN Marg (from Rajghat to Delhi Gate) will also be closed, the traffic police said.
Commuters have been advised to use Aurobindo Marg,Safdarjung Road, Mother Teresa Crescent,Park Street,Mandir Marg to travel between north and south Delhi.
Those travelling between east and west Delhi can use Vikas Marg, Shahdara Bridge and Wazirabad Bridge to reach Ring Road.