The Twelve Apostles of Ilkley Moor

I have walked from Burley moor to Ilkley moor several times, but for some reason I have never come across these before.

Although they are referred to as 'The Twelve Apostles of Ilkley Moor', the circle is in fact on adjacent Burley Moor

The Twelve Apostles stone circle is in a spectacular location above the Cow and Calf rocks.
The archaeologist Arthur Raistrick suggested that there were originally around 20 in the circle. None of them are particularly tall, the largest is less than a metre and a half in height.
The site suffers severe visitor erosion and is regarded as one of the most damaged prehistoric sites in West Yorkshire.