The mound is not a perfect circle, but is made up of a series of sections of parabolas, supporting Prof. A. Thom's assertion of geometry in the design. Around the mound are 12 standing stones which are believed to have been set up the same time. The kerb-stone that lies before the passage has carvings similar to one found on the Orkneys, and another found at Bugibba, Malta.

The beautifully carved Kerb-stone in front of the entrance to the passage-mound.

(Note: The spirals rotate clockwise on the left hand side of the stone, and anti-clockwise on the right).

The Kerb-stones - All the mounds in the Boyne valley have kerb-stones, The Newgrange mound is surrounded by 97 granite 'Kerb-stones', with carvings only visible on a few. It has been pointed out that the stones with the most carvings on are also the most significantly astronomically aligned, leading to suggestions that the carvings have an astronomically significance themselves.

The rear kerb-stone (K52). A line divides the art into two halves.

(Click here for individual images of each kerbstone)

The entrance as it was at the turn of the century.

The entrance after first restoration, but still before the Disneyfication of the 1970's.

The Light-box/Roof-box - Above the entrance passage is a 'light-box', which precisely aligns with the rising sun at the winter solstice of 21st  December, so that the rays touch the ground at the very centre of the tomb for about 20 minutes. Many of the upright stones along the walls of the 19m (62ft) passage, which follows the rise of the hill, are richly decorated.

The light-box combines with other design features so that the light is narrowed with the result that a small 'dagger' of light slides along the floor of the passage towards the inner chamber, where it illuminates it for 17 minutes a year.

Similar carvings as those found on the front face of the lintel of the roof box can be seen at other passage mounds, such as at Fourknocks and Gavr'inis, (both orientated astronomically), which has led some to suggest that this design might have had a significance (rather than just abstract art).

The stone at Newgrange appears to have eight crosses on its face, but a diagram of the stone before reconstruction (below), suggests that there may have once been another cross on the face, which would make a total of nine crosses, the same as at Gavr'inis..

 

The stone above can be seen in the east recess of the cruciform chamber inside Newgrange. It is very similar in style to art seen on lintel-stones at Fourknocks.

The passage slopes upwards towards the centre of the tomb so that the floor-level inside the chamber is at the same height as the ceiling level at the entrance, the passage also undulates from side to side along its length. The combined effect of these two features is that the light that enters the passage is narrowed both vertically and horizontally into a small focused beam of light that only penetrates the internal chamber for a few minutes on the winter solstice.

The stones that cover the passage had small channels cut into them on their upper-faces to keep the passage dry. Similarly, the stones that compose the corbelled roof of the chamber are all sloped downwards on the outside, also presumable to keep the chamber dry. These features highlight the skill of the builders, and lend weight to the idea that the structure was built for long-term use (rather than as a funerary structure).

Inside the heart of the mound is a single corbelled chamber entered through the passage orientated towards the sunrise on the winter solstice. The internal plan is in the form of a cross (cruciform), and is lined with large slabs of rock. The cruciform chamber inside the mound measures 6.5 x 6.2m (21ft 6in x 17ft), has three recesses, and is topped by a magnificent corbelled roof reaching to a height of 6m (20ft) above the floor. In the recesses are three massive stone basins (similar to those found in the temples on Malta), and which presumably served some ritual use. The basin in the back alcove was broken a few hundred years ago by a treasure hunter. (16). Excavations in the central chamber produced the remains of two burials and at least three cremated bodies as well as seven marbles, four pendants, two beads, a flint flake, a bone chisel, and fragments of several bone pins and points.

The cruciform shape of the interior chambers is a common prehistoric design feature, seen in several prehistoric structures from different European sites in Scotland, France and Malta. It is interesting that in several of these locations, large round 'offering bowls' have been found. (Such as Maes Howe, Orkneys and the Tarxien, Malta).

They are distinguished by a long passage leading to a central chamber with a corbelled roof. From this, burial chambers extend in three directions, giving the overall impression in plan of a cross shape layout. Some examples have further sub-chambers leading off the three original chambers. The network of chambers is covered by a cairn and lined outside with kerb-stones.

A common trait is megalithic art carved into the stones of the chambers' walls and roofs. Abstract designs were favoured, especially spirals and zig-zags.

Examples are Newgrange , Knowth, Dowth and Fourknocks  (amongst many) in Ireland, Maes howe in Orkney, 'La Hougue Bie' on Jersey and Barclodiad-y-Gawres in Anglesey.