Tunnel in the Woods

I came across this structure as I walked through the woods, I have no idea of its purpose or origin.   It isn't wide enough to have accommodated vehicles either through or over it and I don't think it would have been strong enough anyway.   But I liked the view through it of the leaf lined pathway and those lovely Holly and Evergreens.
After an extremely sharp frost to start the day and some scattered sleet showers this morning the sun made a welcome appearance this afternoon, but with the  sky clear again now, I think there will be a sharp frost to wake up to in the morning.