Almost 300,000 candidates, from clean-shaven aristocrats in ties to bearded Islamic revolutionaries and Western-trained yuppies, are vying for 197,000 seats on village, town and city councils in what officials have billed as Iran's biggest experiment in grassroots democracy and decentralisation.

``The elections are the greatest symbol of participation and political reform,'' President Khatami, a populist Shiite Muslim cleric elected 21 months ago, said as he cast his votes in a northern Tehran mosque.

Officials said 39 million Iranians, aged 15 years and up, were eligible to vote, at more than 52,000 polling stations.

In heavily politicised Tehran, some 4,200 candidates are competing for 15 seats. Despite the daunting scale, voters at number of polling places around thecapital said they knew in advance exactly how they would cast their ballots.

Most clutched lists of candidates from among the leading slates advertising in newspapers. Others carried hand-written notes to help them find their favourites among the huge computer print-outs listing the hopefuls and their required code numbers.