Anke Mielke digs through her orange garbage bag, sifting through numerous plastic bags and other scraps of trash before pulling out the strangest thing she's found so far on the banks of the Rhine River — a pungent pair of jeans.

Mielke tells DW that she hopes that by cleaning up the riverbank, others will be reminded to take their rubbish with them next time.

"I grew up along the Rhine and I want it to remain beautiful so that others can enjoy it," she says.

Watch video 10:44 What makes the Rhine so beautiful?

Mielke is one of around 60 volunteers who came out on Saturday to pick up trash along the banks of the Rhine River in the western German city of Bonn, which is taking part in the multinational "Rhine CleanUp Day."

A total of 58 cities in Europe are taking part in the initiative that spans the length of the Rhine River, from its source in Switzerland to its end in the Netherlands. It is the second-longest river in Europe after the Danube.

Around 10,000 volunteers came out to pick up garbage in cities along the Rhine on Saturday, Joachim Umbach, one of the main organizers behind the Düsseldorf-based project, told news agency dpa. He added that 9,000 of the volunteers were located in Germany alone.

A volunteer displays a pair of jeans she found while picking up trash along the Rhine River

Fighting back against plastic trash

By the end of the three-hour cleanup event in Bonn, volunteers had filled their orange bags with scores of dirty diapers, used sanitary pads, plastic candy wrappers and even a rusted grill and a tent from the area along the Rhine.

An estimated 1,100 tons of trash floats down the Rhine and ends up in the North Sea every year, according to the event's organizers. A particularly high concentration of microplastics is present in the waters in Germany's Rhine-Ruhr region, which is home to around 10 million people, according to German researchers.

Gabriel and Tamara Lohre, who organized one of the trash collecting areas in Bonn, tell DW they were inspired to take part in the event after hearing about beach cleanups in other countries.

Tamara and Gabriel Lohre, the organizers of one of the Bonn cleanups, hope people will be inspired to pick up their trash

"We want people to see what we're doing here and also to see what needs to be done," Gabriel Lohre says.

Tamara Lohre adds that she thought it was "really great that there are so many small children here, so they learn how important this is."

"Rhine CleanUp Day" organizers hope to repeat the trash pickup day next September.

"We don't think this is going to change everything all at once," Gabriel Lohre says. "But if just two or three people start taking their trash with them, then we've won something."

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