What do you call an arched entrance to a garden? I am not sure if there's a word specifically for garden entrances, but I am willing to bet there's a word for an arched entrance like that. What do you call it?
I call it an archway, or An arch over an entrance or passageway but those can vary a lot in size and materials. If you are speaking very specifically about an arched entry into a garden, I would call it a garden arch or an arbor.
Arbor was the first thing I thought of, but in my mind, it is always meant to be covered in some sort of climbing plant, and it’s not always over a passageway. Arbors can be set over a bench to provide a nice shady place to sit.
Like most words in English, the choice of which one works best depends on the context.