Portugal, Porto, Vila Nova de Gaia, Rabelo cargo boats on the River Douro with the Ribeira area of Porto in the background, Rabelo cargo boats were used for bringing wine from the vineyards in the Dou...

Portugal, Porto, Vila Nova de Gaia, Rabelo cargo boats on the River Douro with the Ribeira area of Porto in the background, Rabelo cargo boats were used for bringing wine from the vineyards in the Dou...

Portugal, Porto, Vila Nova de Gaia, Rabelo cargo boats on the River Douro with the Ribeira area of Porto in the background, Rabelo cargo boats were used for bringing wine from the vineyards in the Dou...

Portugal, Porto, Dom Luis I Bridge or Ponte de Dom Luis I, Double-deck metal arch bridge over the Rver Douro which was opened in 1886, Rabelo cargo boats on the River Douro in the foreground that were...

Portugal, Porto, Dom Luis I Bridge or Ponte de Dom Luis I, Double-deck metal arch bridge over the Rver Douro which was opened in 1886, Rabelo cargo boats on the River Douro in the foreground that were...

Portugal, Porto, Dom Luis I Bridge or Ponte de Dom Luis I, Double-deck metal arch bridge over the Rver Douro which was opened in 1886 and is seen here from the esplanade of the Monastery of Serra do P...

Portugal, Porto, Dom Luis I Bridge or Ponte de Dom Luis I, Double-deck metal arch bridge over the Rver Douro which was opened in 1886 and is seen here from the esplanade of the Monastery of Serra do P...

Portugal, Porto, Dom Luis I Bridge or Ponte de Dom Luis I, Double-deck metal arch bridge over the Rver Douro which was opened in 1886 and is seen here from the esplanade of the Monastery of Serra do P...

Portugal, Lisbon, Belem Tower, 16th-century fortification that served as a point of embarkation and disembarkation for Portuguese explorers and as a ceremonial gateway to Lisbon, the tower symbolizes...

Germany, Hesse, Frankfurt, view of the Main river and the tower of the Kaiserdom Saint Bartholomaus or Frankfurt Cathedral with the Eiserner Steg pedestrian bridge.

Germany, Hesse, Frankfurt, view of the Main river and the tower of the Kaiserdom Saint Bartholomaus or Frankfurt Cathedral with tourist sightseeing boats moored on the waterfront.

Germany, Hesse, Frankfurt, view of the Main river and the pedestrian Eiserner Steg bridge from the tower of the post WW2 restored Frankfurt Cathedral or Frankfurter Dom, the Imperial Cathedral of Sain...