Unknown pub - Please help!

A few years ago I crowdsourced the a few photos of pubs that I could not identify on this blog - to a great success from my readers who identified them all!

So here is another photo from the same collection which we cannot identify. The collection consists of photographs of old Rhymney Brewery pubs, some extending into the Whitbread era but they tend to be in colour.

All we know about this photo is that it was a Rhymney Brewery pub and that it is labelled 'New Inn' and the place name is 'Porthiwithen' which does not appear to exist. Have also tried a few other spellings in Google but to no avail so have decided to put it out to the net for any ideas as to where this is.

Update: After a few years of searching I finally found the former pub, the place is Porth-y-widden in Monmouthshire, just to the East of Llangattock Lingoed

Today the house is called "The Old Inn"