The lighthouse on a tiny island off this ancient fishing town used to be on the mainland.
The small boat with only its mast rising above the waves did not sink. It ran aground and has been covered by the advancing sea.
Both are victims of erosion along Egypt's Nile Delta coastline, as giant dams on Africa's great river prevent formation of land-building sediment.
The Mediterranean is encroaching on parts of the delta, vital farmland for a desert country with only 4% of its land suitable for cultivation and a population growing at more than 1 million a year.
"What land used to be formed in the delta in 10 years, we now lose in one year," said Ahmed Abdel Wahab Khafaga, a government scientist trying to tackle the problem.
He predicted that sea water could eventually reach Mansoura, 30 miles inland from Rosetta, or even Tanta, 60 miles from the sea, over the next two centuries.
Government shore protection authorities have contracted a Taiwanese firm, Ret-Ser Engineering Agency, to stem the tide by building a big breakwater near Rosetta, on the west branch of the Nile 40 miles east of Alexandria.
But even a breakwater will stop the sea's erosion only for about 50 years, Khafaga reckons.
Local officials believe that the barrier, costing $25 million, will help reclamation of 40,000 acres of farmland.
It will also enable Rosetta to build a resort complex to replace one destroyed by the sea, Helmi Mohamed Zayed, chairman of the Town Council, said.
The coastline at Rosetta is currently being pushed back by 500 feet a year, and the sea has moved more than two miles inland in the last two decades.
Khafaga places the blame for erosion on the Soviet-built High Dam on the Nile at Aswan in Egypt's far south, opened in 1965, and the smaller Aswan Dam, built in 1902.
One casualty of erosion at Rosetta is its fishing industry, once the basis of its economy.
Waters at the mouth of the Nile became too shallow for their boats as sand built up at the outlet, because the river's flow was too weak to flush it out to sea. Many of Rosetta's fishermen have now moved to Alexandria.