Rough Roman Memes

The trilithon stones supposedly far too heavy to lift, and also apparently part of just a giant landing/launching pad for spaceships, were placed at Baalbek during its renovation and expansion into a massive temple complex by the Romans.

Baalbek had been inhabited as a minor settlement since prehistoric times, being under the control of Phoenician, Babylonian, Assyrian, Persian and Greek civilizations as history progressed.

At some point during Greek control of the area, a Greek style temple was built there, of different architectural style and smaller than the Roman temple complex that came later.

Eventually the Romans conquered the area and decided to significantly renovate and expand this Greek temple to build their temples to Jupiter and Bacchus, with construction nearing completion around 60 CE/AD, basically eminent domaining the existing settlement's population into the surrounding area.

The trilithon, and most of the remains that can be easily seen today, were put there by Romans.

Ancient Aliens does spend much more time attributing sites built by civilizations or peoples that are not today viewed as direct antecedents to white/western civilization, but Baalbek is a notable exception, one that, at least in the earlier days of Ancient Aliens, was quite a big deal to them.

Also Stonehenge is attributed to Ancient Aliens.

That was one of the foundational myths of Erik von Daniken, who basically (along with Zecharia Sitchin) is the granddad of Ancient Aliens and is featured in many of its episodes.