Take a look at the sites on megalithomania. They are amongst my favourite things. I am off to a few more on my forthcoming visit to Cork this Sunday.

They are basically very large cupmarks - often 30cm across and 15cm deep or so.

They are associated (in Ireland) with holy wells and Brigid worship. No one knows their real (original) purpose but many now are known as wart-wells (they cure them not give them :-)

Some have large stones in the cups that are turned to either cure or curse.

Most archaeos say they are Bronze Age, but I have proof of them being Neolithic.

They are nearly always near to streams or wells. It would be interesting to see if this Cumbrian one is.

There is one on Anglesey in one of the huts on Holyhead Mtn. which I think may have been brought there from Ireland - the stone is certainly not at all local.

There are a few in Scotland too, but the main other places where they are found is on Gotland in Scandanavia and in Lithuania (apparently).