The doorway is still in the modeling process. The source was the gates of the Temple of Bacchus in Baalbek.
The work is already finished, and the full version can be seen at the link:https://sketchfab.com/3d-models/stone-door-baalbek-87c9a471becd4f20a8bd821815d09558
About the temple can be read here: https://en.wikipedia.org/wiki/Temple_of_Bacchus