Her shocking death threw the world's only nuclear-armed Islamic nation into chaos, sparking violence and leading to months of political turmoil that ended in September when Asif Ali Zardari, Bhutto’s widower, claimed the presidency.
"In the tradition of a true Bhutto, she faced certain death rather than abandon her principles or the people," Zardari said in a message to the nation to mark the anniversary.
"The tyrants and the killers have killed her but they shall never be able to kill her ideas, which drove and inspired a generation to lofty aims."
The mourners travelled by train, bus, lorry, car, bicycle and even on foot to mourn the charismatic, Oxford-educated Bhutto - the first woman to lead a Muslim nation - who was hailed in the West as a face of moderation.
Imtiaz Gul, a Pakistani analyst, told Al Jazeera: "She will be remembered for very long, for her charisma, her vision, and for her ability to galvanise people.
"Whoever found him or herself in her company would come out of the meeting very convinced. She left a very impressionable image on almost everybody."
However, Gul was less convinced of Zadari: "I don't think Benazir would have ever thought of leaving her legacy to Asif Zardari.
"I think Mr Zadari would be remembered for destroying, for undermining the party more than anybody else if we were to judge him in years to come."
Mourners from afar
Tariq Waseem, a 25-year-old student from southwestern Baluchistan province, walked about 400km over 10 days with about a dozen friends in order to be at Saturday's event. But unlike his friends, he walked barefoot.
"These are not painful," he said, pointing with pride at blisters covering his soles. "These are a gift from my martyred leader."
One year on, Pakistan's reverence for Bhutto continues unabated - television programmes about her life have been running for days, and the government has issued a 10-rupee coin and stamps bearing her portrait.
The government has declared Saturday a national holiday in Bhutto's honour, and events were scheduled in cities nationwide.
Bhutto is buried alongside her father Zulfikar Ali Bhutto, a former premier who was hanged in 1979 by the country's military regime. Her brothers Shahnawaz and Murtaza, who died in violent circumstances, are also in the tomb.