What is the function of the traditional flat-bottomed rabelo boats in the Douro Valley?

Answer

Transporting harvested grapes downriver from steep vineyards

The geography of the Douro Valley, characterized by steep, precipitous, terraced vineyards, necessitates unique methods for moving the product. Traditionally, the harvested grapes, once pressed, were transported down the Douro River using specialized vessels known as rabelo boats. These flat-bottomed boats were essential for navigating the river, moving the wine—or sometimes the must/grapes—from the remote quintas (estates) in the upper valleys downriver to the cellars and lodges located closer to the Atlantic coast, although this method is largely superseded by modern transport today.

What is the function of the traditional flat-bottomed rabelo boats in the Douro Valley?
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