The 1/2 column surround, below, could date as far back as the Romans.
This sweet little door is only about 4-5 feet high. It has a hodge-podge of brick & stone as a surround, which creates an interesting pattern. The bright color of the door & it's flowers completes this picturesque portal.
It is not uncommon to find very low doorways. Medieval entries were often not very high, even though elaborate in design.
While some doorways are low, there are certainly others that are quite high. I would guess this grand example to be about 9 feet in hight with a simple yet elegant surround.
Another rather tall door has a very elaborate surround. Note the sculptural relief of the crossed olive branches above the door.
Below is a good example of a very low doorway datong to the middle ages. The average person of today would have to stoup to enter this ancient abode.
Lastly, here is as simple a surround as could be found, enclosing a lovely old Victorian door.