Flights and trains were suspended, shops pulled down their shutters and hospitals worked on emergency staff on Wednesday in Greece's first big anti-austerity strike since a coalition government took power in June.
Called by the country's two biggest unions representing half the four-million-strong work force, the walkout is expected to bring out thousands of Greeks to the streets to protest at a new round of belt-tightening demanded by EU and IMF lenders.
"The new measures are unbearable, unfair and only worsen the crisis. We are determined to fight until we win," said Costas Tsikrikas, head of the ADEDY public sector union.
"We call on all workers to join us in the march against the policies that the troika is imposing."
The traditional summer break has allowed the conservative-led government of Prime Minister Antonis Samaras to enjoy relative calm on the streets since narrowly coming to power on a pro-euro, pro-bailout platform.
But ADEDY and its private sector counterpart GSEE were predicting a big turnout on Wednesday to end the seasonal lull.
"This strike is only the beginning in our fight," said ADEDY unionist Despoina Spanou.
About 3,000 police - twice the number usually deployed - will stand guard in the centre of Athens as authorities brace for the rioting that has marked past rallies. Athens last witnessed serious violence in February, when protesters set shops and banks ablaze as parliament approved an austerity bill.
Ahead of marches scheduled later in the day, ships stayed docked, museums and monuments shut to visitors and air traffic controllers walked off the job for a three-hour stoppage.
Much of the union anger is directed at spending cuts worth nearly 12 billion euros (9.6 billion pounds) over the next two years that Greece has promised the European Union and International Monetary Fund in an effort to secure its next tranche of aid.
The bulk of those cuts are expected from slashing wages, pensions and welfare benefits, heaping a new wave of misery on Greeks who say repeated rounds of austerity have pushed them to the brink and failed to transform the country for the better.
A survey by the MRB polling agency last week showed that more than 90 percent of Greeks believe the planned cuts are unfair and burden the poor, with the vast majority expecting more austerity in coming years.
But with Greece facing certain bankruptcy and a potential euro zone exit without further aid, Samaras' government has little choice but to push through the unpopular measures, which have also exposed fissures in his fragile coalition.
With Greece in its fifth year of recession and no light at the end of the austerity tunnel, analysts say Greek patience is wearing thin and a strong public backlash could tear apart the weak conservative-led coalition.
"What people want to tell Samaras is that they are hurt and Samaras could use this to demand concessions from the troika," MRB polling director Dimitris Mavros said.
"The people are willing to give the government time, but on certain conditions like cracking down on tax evasion and securing a bailout extension. If the government succeeds in that, its life will also be extended."
(Additional reporting by Tatiana Fragou; Writing by Deepa Babington; Editing by Angus MacSwan)