There were three major challenges involved in the building of stonehenge...
1) Selecting and shaping the 'right' stones.
2) Transporting the stones to the Salisbury plain (some came from south Wales).
3) Erecting the stones to acheive the desired monument.
Because they did not have modern tools to quarry and move the largest stones, or to excavate large areas. The early stones were identified as having been brought some 220 km (140 miles) from where they were cut.
It does appear to have been an arduous venture. However, nobody knows for sure how Stonehenge was constructed (at least in terms of building techniques).
The Babylonians didn't build Stonehenge.
Stonehenge is thought to have been built by the beaker people.
Oh dear ! Methinx someone is having a little dig at our US cousins ! Native Americans & Stonehenge have no connection.
Stonehenge is pre Roman, begun about 5000 year ago
No they did not
limestone
The blue stones at Stonehenge came from the Prescelly mountains in south Wales.
By the use of sophisticated geometric design and prefabrication techniques.
No. It is not clear whether Merlin actually existed.
Nothing really, it was there long before the Romans ever came to Britain.
England
No, actually it was cultists who worshiped the sun.