Greeks are heading to the polls on Sunday to elect their first post-bailout government and the 19th since the restoration of democracy in 1974.
The snap elections were called by Prime Minister Alexis Tsipras after his SYRIZA party suffered a significant defeat in the European and local elections held in the country last month.
Opinion polls published in the run-up to the vote point to a clear win for main opposition New Democracy and its leader Kyriakos Mitsotakis.
The last time general elections were held in mid-summer was in August 19, 1928, while Greeks also voted to select their lawmakers in 1910 (August 21) and in 1875 (18 July).
All 300 seats in the Greek Parliament will be contested with 20 parties and coalitions running in the elections.
The Interior Ministry said 21,478 polling stations opened at 7 a.m. and will close at 7 p.m.
This will be the first national election and third election in total since the voting age was lowered to 17, and the number of parliamentary constituencies was increased from 56 to 59.
During the day 9,903,864 registered voters will be called to exercise their electoral rights, of whom 519,227 are aged 17 to 21.
Roughly one-fourth of the electoral body is above the age of 71, 1,533,588 voters are in the 60-70 year-old bracket and 1,928,046 are aged 48-59 years old.
Greek nationals living abroad cannot vote in the general elections from their country of residence.
Right after ballot boxes close at 7 p.m., all TV channels will publish a joint exit poll, while the first safe estimates on the official results by Singular Logic, the Greek tech firm tasked with vote tallying, are expected two hours later, at 9 p.m.
A big question in Sunday's election will be the abstention rate due to the timing of the polls in the middle of the summer holidays. In June's European elections, abstention came to 41.3 percent, which was a slightly better than the last general elections in September 2015, when it came to 43.8 percent.