Organisers including the World Wide Demonstration for Freedom and Europeans United for Freedom had called for people to come from other EU states.
Flags from Poland, the Netherlands, France and Romania could be seen in the crowd.
“What has been happening since 2020 has allowed people to wake up to corruption,” said Francesca Fanara, who had travelled from Lille in northern France,
“I have come to march together.”
“It’s a health dictatorship,” said Adolfo Barbosa from Portugal.
“It warms the heart to see these people here.”