Marco notes that the nearest basalt outcrop was a few hundred meters from the site, and that the stones, which were three to six feet (one to two meters) in width, would have weighed over 200 pounds (90 kilograms) at times.

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And if someone were actually on a spacecraft traveling through the region, chances are the next nearest slab of rock would be at least a few hundred thousand kilometers away.

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He had dragged his family to this remote outpost, a hundred miles and a two-day trek from the nearest railroad station.

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