1. 1000 ton stones
Each stone is carved from granite rock in a shape, perfectly cuboid. Also, to carry those stones from the quarry to the construction site, workers had to cross the Nile. It's impossible for a human to move a 1000 ton stone and cross the river carrying it. Even if it were a group of humans who brought the rocks across the Nile, it still seems practically impossible.
2. Alignment of individual pyramids
All the three great pyramids of Giza face the exact North. The other three sides of the great pyramids face precisely East, West and South direction which means that when they built the pyramids, they had some sort of directional assistance. What's surprising is that there were no compasses, back at the time. How did the Egyptians calculate directions without an outsider's help? The question still baffles our mind.
3. Alignment of the three pyramids
All the three pyramids are linearly assigned. They all have an entrance, and about every monument, there is a conspiracy theory that the pyramids are interconnected by a secret web of tunnels. Taking our eye off the conspiracy theories, all three pyramids are said to be aligned with the three stars in the belt of Orion in such a way that the tip of all three pyramids points toward their respective stars.
4. Alignment of all historic sites around the globe
Different civilization sites that have been dug out are Giza, Siwa, Tassili n' Ajjer, Paratoari, Machupicchu, Ollantaytambo, Nazca, Easter Island, Aneityum Island, Preah Vihear, Sukhothai, Pyay, Khajuraho, Mohenjo Daro, Persepolis, Ur, and Petra.