Campaigners have built a 30ft warship from single-use plastic rubbish collected from UK beaches to highlight the threat it poses to the oceans.
Surfers Against Sewage (SAS) unveiled the sculpture as they called on the public to reject plastic items designed to be used once and then thrown away, which can end up littering the seas and coastlines.
The environmental charity, which mobilises 25,000 beach clean volunteers annually around the UK, has revealed the most commonly found single-use plastics on UK beaches are bottles, coffee cups and lids and plastic cutlery.
Other common litter includes plastic straws and stirrers, packaging for on-the-go food, plastic bags, toothbrushes, cotton buds, drinking cups, condiment sachets and balloons, SAS said.
A survey for Surfers Against Sewage of more than 2,000 people suggests that a quarter do not realise that not all plastic can be recycled.
Many are using plastic bottles and takeaway containers on a weekly basis, and almost a quarter (24%) use at least three cotton buds a week, it suggests.
The charity said micro-particles from plastic waste are creating ocean sludge, killing plankton and contaminating the food chain.
A growing mass of marine plastic in the North Pacific - dubbed "Wasteland" - is made up of a soup of these tiny particles of disintegrating plastic interspersed with bigger items of rubbish.
SAS has created the 30ft SAS Wasteland Warship out of three tonnes of plastic collected from beaches in the UK to highlight the issue.
It has been installed on the picturesque Cornish coastline at Marazion Beach, framed by St Michael's Mount.
Hugo Tagholm, chief executive of SAS, said: "In a remote area in the North Pacific lies one of the most catastrophic man-made disasters to have ever affected us.
"Five times the size of the UK, Wasteland is growing and threatens to destroy us and our planet, yet it is a 'country' not many know about.
"Our Wasteland Warship is designed to highlight this, helping to spread the message about what is one of the greatest environmental threats of our time.
"There are easy steps we can all take join the resistance against the flow of plastic feeding Wasteland.
"Whether that's refusing throwaway plastics wherever we can, taking a refillable bottle with you instead of buying single-use plastic bottled water, reusing plastic bags on your weekly shop at the supermarket, or making sure you recycle more, we all have our role to play."
The campaign comes as scientific analysis suggests more than eight billion tonnes of plastic has been produced since the early 1950s and most of it is buried in landfills or litters the oceans and countryside.