Opponents of nuclear power formed a 120-km (75-mile) human chain between reactor sites in Germany on Saturday to protest against government plans to extend the power plants' operation.
Around 120,000 peaceful demonstrators, according to police and organisers, linked arms in a chain running between the northern towns of Brunsbuettel and Kruemmel that passed through the city of Hamburg.
"Today will spark a countrywide chain reaction of protests and resistance if the government does not reverse its atomic policy," organisers said in a statement.
Chancellor Angela Merkel's centre-right government has said it wants to extend the lives of nuclear plants, although politicians differ over how many years to add to the plants' lives beyond 32 years. Between eight and 20 years are suggested.
The government is aiming to agree in October on a wider national energy plan.
Protesters hope to draw attention to the issue before a May 9 regional election, after which they fear Merkel's coalition will move to extend the reactors' lifespan.