[Archaeologists] scanned satellite pictures from across the east coast of America. Several sites appeared worth following up, but they had to decide on one for a dig. In the end they opted for a headland, almost the very western tip of Newfoundland, 400 miles further south and west than the only known Viking site in North America. It overlooked two bays, offering protection for ships from any wind direction. Parcak saw oddities in the soil that stood out - patterns and discolourations that suggested artificial, man-made structures, possibly even Viking longhouses, once stood there.
...
A blackened rock testified to intense temperatures. Beneath it were piles of charcoal mixed with cooked bog iron - an iron deposit that needs to be baked to drive off impurities and allow the iron to be extracted for smelting. Surrounding the hearth appeared to be a turf wall of the kind built by Viking settlers across the North Atlantic.
— Dan Snow, The Vikings Uncovered