Sizewell C: Heart demonstration for Minsmere reserve
Hundreds of people formed the shape of a giant heart to support a nature reserve and voice concerns at plans for a new nuclear power station.
EDF Energy wants to build two reactors next to the existing Sizewell B in Suffolk near Minsmere reserve.
The RSPB, which organised the Love Minsmere Festival, is opposed to Sizewell as a location for a new power station.
EDF said it was sharing its work with environmental groups.
Minsmere reserve provides reedbed, wet grassland and heath habitats for a variety of wildlife including marsh harriers, otters, water voles and bearded tits.
In the first three months of next year, plans for the new plant Sizewell C will go to the Planning Inspectorate and then on to the secretary of state, and campaigners at the event fear the plant could damage the wildlife habitat.
One campaigner at the event told the BBC: "There's a great variety of wildlife all year round. Why spoil the place? That is my message to EDF."
The event also attracted celebrities including former BBC Breakfast presenter Bill Turnbull and actress Diana Quick.
Mr Turnbull said: "I'm angry, I'm mad, because the idea that anyone would sit down and look at a map and see how near the reserve is and say 'let's built a nuclear power station here'. You would have to be bonkers."
RSPB Suffolk area manager, Adam Rowlands, said: "The RSPB does not believe that Sizewell is a suitable position for a new nuclear power station."
Therese Coffey, Conservative MP for Suffolk Coastal - which includes Sizewell and Minsmere - told the BBC a survey found that most of her constituents support nuclear power.
"The majority of people who responded wanted it, but the jury is still out as far as to whether EDF is able to satisfy the environmental demands," she said.
An EDF spokesman said the company will "fully assess the potential impact the Sizewell C project could have on Minsmere and the wider network of internationally protected areas as part of the environmental impact assessment for the project".