Thousands of union activists have marched through French cities as airport employees, teachers and other workers joined nationwide strikes, cranking up pressure on the government to scrap changes to the national retirement system.

As the strike entered a sixth straight day, commuters and tourists in Paris used apps, shared bikes and found other creative ways to get to work, school and museums.

France Strikes
Parisians walk, ride bikes and skateboards (Francois Mori/AP)

Many commuters still express support for the strike, fearing their own pensions will shrink under President Emmanuel Macron’s new plan, but some admitted their patience is wearing thin with the transport disruption, and with train workers who are striking to keep their right to retire years earlier than other workers.

Under a sea of red union flags, thousands of activists and workers from across the economy, young and old, gathered at the gold-domed Invalides monument for a march past the Montparnasse neighbourhood to southern Paris.

Paris police ordered shops and restaurants closed on roads around the gold-domed Invalides monument, fearing violence on the fringes of what government opponents hope is another mass march. At least 800,000 people turned out for demonstrations around France when the strike movement kicked off last Thursday.

Protests are being held around the country on Tuesday, with union activists waving red flags from Marseille on the Mediterranean to Lille in the north.

France Strikes
Protests in Paris (Francois Mori/AP)

Unions fear Mr Macron’s retirement reforms will force people to work longer for smaller pensions, even though the government says it will not raise the official retirement age of 62.

Nationwide, only about a fifth of French trains ran normally on Tuesday, frustrating tourists who found stations empty and services cancelled. Most Paris subways were at a halt, and just one bus in three was running normally. Paris roads were jammed with traffic.

Some commuters used ride-sharing apps or stayed with friends and family near their offices. Others dusted off old bicycles, tested electric scooters for the first time or walked several miles to avoid sitting in traffic.

France Strikes
Commuters wait to catch a subway train in Paris (Francois Mori/AP)

Air France, the national carrier, said more than 25% of its domestic traffic was grounded on Tuesday by the strike, along with more than 10% of medium-range flights, on the orders of the French civil aviation authority.

About half of Paris schools were closed and others had many classes cancelled.

Overall the number of striking workers is lower than last week, and the stoppage may falter after the government releases long-awaited details of the retirement plan on Wednesday.

Emmanuel Macron
Emmanuel Macron (Francisco Seco/AP)

The strikes are a big test for Mr Macron, who promised to reform France’s retirement system while campaigning for president in 2017.

He has ordered two years of consultations with workers and employers about the new system, which aims to blend 42 separate retirement plans into one.

He argues that the reform is needed to keep the pension system from sinking into billions of euros of debt as lifespans lengthen, and to make it more universally fair to all workers.

Unions fear the changes are part of a broader mission to dismantle hard-won worker protections.