It’s likely that extraterrestrials have been to Earth multiple times throughout our history. There happens to be physical evidence to support this claim.
Some of the most popular structures attributed to extraterrestrial creation are Stonehenge, the Easter Island Heads, and the Pyramids of Giza.
What we’ve learned about Stonehenge is that it was built as an astronomical observatory for predicting eclipses. Consisting of 60+ stones over 10 ft. tall, and weighing upwards of 26 tons each, makes aliens a plausible creator.
The Easter Island Heads are stone statues carved from volcanic rock reaching up to 40 ft. tall and 75 tons- each. The mystery of how these massive monoliths got to their location has perplexed mankind since their discovery. ALIENS? (it’s possible).
The Pyramids of Giza, popularly known for being one of, if not the most difficult structure to ever be built. While aliens are a common theory for their creation, it’s not far-fetched to say that ancient slaves were used by Egyptian rulers to build these massive structures.
There are many realistic and logical explanations for each of these monuments, however it isn’t entirely out of the question to assume that extraterrestrials might have had some involvement in the creation of these massive wonders.