During the past 100 years, it has attracted millions but a beautiful tourist spot is threatened with being swallowed up by the sea.

A conservation group has called for action to preserve the meandering route of the Cuckmere in its estuary near Seaford.

The South Downs Society wants the Environment Agency to save the stunning feature for future generations.

The agency is reviewing sea defences in the area and has sent a report to groups with an interest in the site.

The report outlines three options - do nothing and allow the meanders eventually to be flooded, replace flood defences and prevent this or remove man-made banks and allow the river to run through its curving route again.

If nothing is done within 50, the meanders could be gone.

The estuary is a site of special scientific interest, designated heritage coast and part of the Sussex Downs area of outstanding natural beauty.

Environmental organisations including the National Trust and English Nature support returning it to its natural mudflats, salt marsh and meadows.

Dr Basil Lindsey, of the South Downs Society, formerly the Society of Sussex Downsmen, said this would be good for wildlife but not for the hundreds of thousands of visitors to the estuary.

He said: "Our concern is the attractiveness of the site. It is a place with lovely access to the sea for walkers and cyclists.

"People can use the meanders for sailing and for enjoyment. We want to see that preserved.

"Like King Canute, you can't resist the tide of the rising sea levels for ever. But we can for quite a long time."

An Environment Agency spokeswoman said the final report will take into account any comments or questions raised during the consultation process.