Zimbabweans are voting for the country’s next president – and for the first time in nearly 40 years Robert Mugabe is not on the ballot paper.
Long lines formed outside many polling stations in the capital, Harare.
Thousands of election observers will be watching to ensure there are no irregularities after opponents’ claims that the process is biased against them.
Past votes have been tainted by violence and intimidation.
The two key candidates are current president Emmerson Mnangagwa, who took over from Mr Mugabe in November, and MDC Alliance leader Nelson Chamisa.
In total, there are a record 20 presidential candidates.
Cheers and whistles greeted Mr Chamisa, 40, a lawyer and pastor, as he arrived at a polling station just outside the capital.
The first election without Robert Mugabe marks an historic moment for the country
Nelson Chamisa held his ballot paper in the air as he voted in Harare.
Mr Mugabe had led the country with an iron first since independence from the UK in 1980, but the 94-year-old was forced to resign last year after a military coup.
Emmerson Mnangagwa is hoping for a mandate to continue as president.
He cast his vote on Monday at a school in the constituency of Kwekwe, around 125 miles (200km) south of Harare.
Mr Mnangagwa said he wanted a country where people had “freedom to express their views, negative or positive”.
He also brushed off Robert Mugabe’s snub on Sunday, telling reporters: “He is a citizen … He can engage me anytime.”
A day before voting began, Mr Mugabe
indirectly endorsed Nelson Chamisa despite him being from the opposition he once fought against.
Summoning journalists to his mansion for a meandering statement, he said: “I will not vote for those who have illegally taken power.
“I cannot vote for those who have tormented me… I cannot vote for ZANU-PF.
On Mr Chamisa, he added: “He seems to be doing well at his rallies. I wish to meet him if he wins.”
Mr Mugabe also turned out to vote on Monday.
He struggled to walk, but raised his first before entering the polling station as scores of people gathered outside chanting in support.
“I just want to see him face to face, even shake his hand as someone I have supported all my life. I still feel like he is my hero,” said voter Jacob Mucheche.
However, there were early complaints from the MDC party of “voting going at a snail’s pace” in the country’s second city of Bulawayo.
David Coltart, a supporter of Mr Chamisa and a former government minister, said on Twitter that it was “a means of suppressing the urban vote”.