HAMBURG, Germany  Naples’ garbage  the plastic Ferrarelle water bottles, the soggy copies of Internazionale magazine, the decomposing kitchen compost  has ended up here, waiting to be dumped into an incinerator on the outskirts of this tidy German city.

For months, mountains of rotting trash have grown in the streets of southern Italy because the region has run out of places to put it. So for the time being  11 weeks, actually  a 56-car train will arrive in Hamburg every day after a 44-hour journey, each bearing 700 tons of Neapolitan refuse.

“We are doing this because we were asked to provide emergency aid, but we will do it only for a few months, not years,” said Martin Mineur, the director of two of Hamburg’s incinerators, as a steady stream of trucks carrying garbage from the train station roared by. “This is not a long-term solution. Italy will have to solve Italy’s problem.”

But Italy’s problem has echoes in all of Europe, where Naples looks increasingly like a foul-smelling version of an untenable past, and Hamburg its future. Despite population growth, Hamburg produces less garbage today than it did almost a decade ago. What it does generate is either recycled or removed to high-tech, low-polluting incinerators.