At least 3,000 people formed a chain of light in Vienna on Wednesday to protest against the formation of a government that includes the far-right Freedom Party.
Demonstrators holding flickering candles, torches and bicycle lamps encircled the capital's government district.
"Our republic's most powerful political offices should be exclusively reserved for trustworthy people who are not in the slightest connected to right-wing extremists," said Alexander Pollak, spokesman for SOS Mitmensch, one of several human rights groups which organized the demonstration.
It was the biggest protest in Austria since coalition talks between the conservative People's Party (OVP) and the Freedom Party (FPO) started two weeks ago.
Organizers estimated the number of people taking part at 8,000 to 10,000, the police at around 3,000.
"We are here because they (the FPO) feed hatred and want to divide people," said Brigitte Griesser, holding a candle.
But the protest was far smaller than unrest 17 years ago, when the FPO last formed a government with the OVP and more than 100,000 took to the streets.
"[The shift to the right] has become a European trend... it's no longer just an Austrian issue and that's why it is not that controversial any longer," said protester Juergen Pucher.