The Longyou Grottoes:
The Longyou Grottoes consist of manmade 24 caves, carved out of siltstone in Fenghuang Hill, near the village of Shiyan Beicun, China. Discovered in 1992, it is estimated that these caves are over 2,000 years old. Their construction isn’t documented anywhere in history, and no one really knows what they were for.
or they are respectful that not all religions utilize the same calendar...
"When in Rome..."
...I use my own d@$% calendar, and I expect everyone else to accommodate me!!!!!
Darwin has nothing to do with historical timelines.
https://en.wikipedia.org/wiki/Sacsayhuam%C3%A1n
What we're talking about is the Norse settlements leading to the settling of the North American continent. Greenland because of it's proximity to N. America is the reason it's included.