Possible Plunge Pool in Woods on the Isle of Wight

Thanks to Mr. IW Archive for his help in uncovering this feature and for hosting such a wonderful lunch, consisting of tasty sausages and bacon over an open fire.
This feature has steps in one corner, a pipe entering in another corner and the sides and bottom are coated in a cement rendering. The north side is composed of in situ rock, while the other three sides a constructed of random rubble stone blocks, rendered with a cement layer.

[@ISLEOFWIGHTARCHIVE]

Credit to whomever opened up the site to expose it's features.

[@AurmazlZudeh]

How long ago do you think it was used last?

[@RevengeLawn]

probably Victorian times.

[@ISLEOFWIGHTARCHIVE]

Looking at the mature tree in the top corner that most probably wasn't there when this was constructed tells you how long ago it was constructed/used.