It’s an EC!

The answer to the small building quiz.

The building is an outside earth closet, as they were known here.  A double throne room as Mark so elegantly puts it in his comment.  So these were what was used when there was no flushing loo.  The holes at the base were for some skivvy to rake out the soil into the little walled in midden outside the back of the building.  I’m not sure about the wall, perhaps it was there to prevent woodland animals (pigs (hogs)?) from spreading the stuff all around the place.

There are some good lumps of stone for the lintels and corners (some people will know them as quoins).  Millstone grit is very plentiful as an outcrop rock around here and is/was used extensively all around here as a durable building material, so cheap you can even afford to build your EC from it!

The fisherman is in the bottom right-hand corner, next to the rocks that look like the reflection of a heron.