Have just checked and when looking along the line of the cursus in the opposite direction to the Samhain ,Imbolc orientation , the sun will rise just to the south of the prominent Deuchary Hill on the Beltane (May 1 )and Lughnasadh August 1 ) . This is not necessarily expected as it is due to the the differing heights of the horizon . What it does is double the likelihood of intentionality .
Removal of whins from the cursus and trees either side have given an improved view of the monument and possible orientation on North Ballo Hill . The declination is -15.8 and indicates where the sun would rise on the cross quarter days of Imbolc and Samhain whether this was intentional or mattered to the builders is open to debate .Originally considered to be a Roman vallum . It extends 2.3 k although it may originally been even longer .
RC dates from 1993 confirmed it being pre Roman giving a date of 3600 BC.
The building of the monument began at the NW with a sub circular burial mound ,subsequently an 80 m –long barrow was added to the SE. a bank on the same alignment as the barrow followed by realignment to the S.The monument was then constructed in segments with gaps in the bank and ditches breaking the monument into five sections.
Cleaven Dyke Cursus
The Ordnance Survey get it wrong once again! The forest clearances are all in the wrong places and they manage to miss out a once tarmaced track, but map the route of a small path- hmmmmm. Travelling south on the A93 from Blairgowrie I stop at one of the small and very muddy lay-bys at the North Wood and then head roughly northwest along a track which according to the map runs along inside the Cleaven Dyke. However, these woods are fairly sparse and light and checking either side of the track doesn’t reveal much. I reach a crossroads in the woods and switch on my GPS to try and work out exactly where I am. I head south to where the cursus should be. Walking down through the trees a huge gap opens up on the right and that’ when the hair on the back of my neck stand up- o h m y g o d- I’ve read a bit about this site- how high it is, how long it is, but nothing prepares you for the sheer huge scale of this sacred monument. The mound itself is about 2 metres- there are bushes growing all along the ridge giving it a height of about 3 and a half metres! The whole monument including furrows, ditches and mound is about 60 metres! Standing next to the mound running way off in either direction I feel very humbled and very very small. It’s a glorious July evening and I start to walk the dead straight line of the cursus towards the dead ends. The sun beats down. I walk the line of the cursus. I walk the mound. I walk the ditches. I walk in the sun. I walk in the cursus:kursus:mursus:murmur:mu:mur:mu:ur.
Kenneth Brophys 1999 article for British Archaeology.
Although the article is on cursus monuments in general there a quite a few references to the Cleaven Dyke, which he describes as "one of the most awe-inspiring surviving relics of Neolithic monumentality left to us today".