Oh, and that the 21st century is a way of counting centuries of the west, that was just being invented around that time, that would be implemented in Japan about 4 centuries later
The first western style skyscraper was built in 1890 and demolished in 1923.
But Japan had pyramids long before that, there are speculations that the underwater pyramids of Yonaguni could be the remains of a civilization 5 thousands years old
As far as I'm aware, the all but universal consensus among archaeologists and scholars (and the Japanese government) is that the "underwater pyramids" of Yonaguni are entirely natural.
I was simply pointing out that megalithic structures have been part of ancient Japan either they were natural or not, skyscrapers definitely not.