Humans have long been obsessed with the possibility of alternate universes, and a way to instantaneously travel between this one and the next. This concept was popularized by the science-fiction TV show Stargate, and as recently as 2015, NASA admitted to having spent at least a decade researching access points to places outside our world, our universe, even beyond space and time as we know it.
The Stargate of Anuradhapura
Conspiracy theorists noted that the stargate of Anuradhapura had near-identical shapes and symbols to those found at Abu Ghurab in Egypt and La Puerta de Hayu Marka in Peru. The most striking similarity, it was said, as speculation around Sri Lanka's stargate reached its peak, is its proximity to water. The nearby Tissa Weva reservoir, built in 300 BC, has been thrown around as conclusive evidence, since both Abu Ghurab and La Puerta de Hayu Marka were also built near water, which, according to the stargate theory, allowed extra-terrestrial beings to process gold from Earth's water.