Climate activists occupy Erasmus Bridge in Rotterdam during World Port Days

Roughly 100 people gathered on the Erasmus Bridge in Rotterdam as part of a protest organized on Friday by environment activist group Extinction Rebellion. The protestors blocked traffic on the bridge in both directions in an effort to divert attention away from World Port Days, an open event at the Rotterdam Port, the largest in Europe by volume, and the tenth largest port in the world.

"The Port of Rotterdam is responsible for 20% of all greenhouse gases in the Netherlands," Extinction Rebellion said on Friday afternoon, shortly after the protest began. The activists flew a banner that stated, "Recover the Harbour," in Dutch.

Police told newswire ANP that there were no plans to break up the protest, even though traffic was blocked for both private vehicles and public transport services. Bicyclists and pedestrians were able to pass along the bridge as of 2:30 p.m., according to Rijnmond.

"Demonstration is a fundamental right. We are present to ensure World Port Days and the protest happens smoothly and safely," a police spokesperson told ANP. They will be allowed to remain as long as they do not pose a threat to public order, police told Rijnmond.

Friday marked the start of the three-day World Port Days event, which drew about 350,000 visitors last year. The event was not disrupted on Friday, with visitors able to access the site using the Willemsbrug instead.

It is the 46th time that the annual event has been organized. "Through countless quay activities, shows on the water and excursions, visitors discover the versatility, innovations and career opportunities of the port of Rotterdam," the port stated on its website.

The activities on Friday include demonstrations by a Rotterdam sailing team, presentations from the Navy about submarine warfare and piracy, emergency exercises, and piloting ships in and out of the port. There will also be demonstrations throughout the weekend from the all-electric boat racing championship series E1.

Saturday, the WaveRunner performance team, Dutch River Riders, will give a show, while ships will participate in a parade for a children's hospital. The parade will include a light and music show. The Navy will help close the event with a paratrooper demonstration on Sunday.