If the weather is good, Stewart can clearly make out the French coast and Cape Gris-Nez from the windows of the bed and breakfast he runs at Sandgate, a seaside resort near Folkestone.
Only 50 kilometers separate England from France at this point.
But when the mist covers the horizon like today, you can't see a thing.
So, sitting in front of his computer, the 72-year-old man has fun tracking down the presence of boats invisible to the naked eye, on the Internet.
And there are dozens of them.
Ferries, freighters, barges, small moving points on this shipping route, one of the busiest in the world.
“A highway,” he says.
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