Show on mapThe kilns are adjacent to the remains of a quarry, and can be found fairly easily from the Commondale road.
There are two entrances with short tunnels leading into the kilns, the right hand tunnel is mis-shapen and will likely collapse in the future.
The kilns themselves are collapsed, but there are the remains of the entances to the left and right at the end of the tunnel.
http://www.docbrown.info/docspics/idig/idigpage14.htm
‘Doc Brfown’ speculates that these are for burning Bracken to produce fertilizer ash due to the redish discolouring in the backs of the kilns.
There are two sizeable quarries right behind the kilns.
http://goo.gl/maps/ifRTG
Although that doesnt mean the couldnt have been used at a later date for another purpose.