There's a bunch of theories that suggest that the North pole of the Earth was once in a different place. They point to two main mechanisms - intermediate axis theorem, which is the thing where the little rotating wingnut on the ISS periodically flips its axis while maintaining its rotation. The other is decoupling of the crust, where the crust as a whole decouples from the mantle and just rotates suddenly. One piece of data that is often used to suggest this happened (and caused the collapse of unknown civilizations) is that one can analyze the orientation of ancient monuments and show that they, at greater than chance rates, are aligned to a point that is not at the current North pole. But if we're assuming there's a planetary civilization building the monuments in the first place, shouldn't we also consider that there could have just been some incredibly important site all these monuments were aligned to?