The Callanish Stones are believed to have been erected around 4,000 years ago . This is Calanais I which consists of 50 stones with the largest in the centre being 16ft high and roughly 5.5 tonnes in weight
A tomb was added at the centre of the circle around 1500bc .
The alignment of the stones are thought to have been used to mark the significant points of the lunar cycle .
There are another lesser known 2 stone circles nearby , Calaniais II and III which consist of 20 stones and 10 stones respectively