Vimaras, vaitmanas and vaitmaras are the spacecraft units created long before the people of Earth of Midgard started developing spaceships of their own, and which still outperform the latter.
These three are commonly known as "the sky chariots" - and were commonly used to travel to other planets that didn't have the galactic gates - or for the purposes of transporting goods for sale.
The sky chariots slightly differ between each other, depending on the civilization building them; but yet, the main principle and their forms remain the same - such a chariot would have a form of pyramid on the outside, and would be a self-conscious machine inside. The exact principle of its' operation is still unknown to many, although some say they do depend on some sort of electromagnetic power.
With that being said, the sky chariots still have nothing to do with Egyptian pyramids.