Knowth is the largest monument of the World Heritage Site, ‘Brú na Bóinne’. It is found 8.4 km west of Drogheda in the Boyne valley complex. It consists of a large mound and 17 smaller satellite tombs. The mound is about 12 metres high and 67 metres in diameter. The Great Mound has two passages with entrances on opposite sides, the western passage is 34 metres long and the eastern passage is 40 metres long, ending with a cruciform chamber.
The large mound has been estimated to date from 3200 BC. The passages are independent of each other, leading to separate chambers. The eastern passage arrives at a cruciform chamber, not unlike that found at Newgrange, which contains three recesses and stone basins. The western passage ends in an undifferentiated chamber, which is separated from the passage by a sill stone.
Like Newgrange, the construction of Knowth was an incredible feat by an obviously skilled, knowledgeable and organised race.
A ring of 127 kerbstones encircles the base of the enormous mound. Although three are missing, the 124 remaining kerbstones represent the amount of work required to put them in place. The Kerbstones are generally oblong in shape and average 2.5 metres in length. The slabs used for the kerb and chamber construction are said to have been transported at least thirty kilometres from Clogher Head, more than likely by boat. Other materials used to build Knowth were sourced from locations far from the Boyne Valley. Round granite cobbles were collected from the shore around the Cooley peninsula, some sixty kilometres to the north. The chunks of quartz found spread around the entrances came from Wicklow, sixty kilometres to the south.
The eastern passage of the Great Mound at Knowth measures 40 metres, making it the longest megalithic passage in western Europe. At the end of the passage is a cruciform chamber with a wonderful corbelled roof similar in style to Newgrange. Twin pillars guard the right-hand recess, where a beautifully engraved stone basin, the finest example known in Ireland, was discovered. The basin, which is 1.4 meters in diameter, is much too large to have been taken into the monument after it was constructed, so the chamber is thought to have been built around the basin. Some believe this basin to be ‘The Cauldron of Dagda’ – one of the four treasures brought to Ireland by An Tuatha dé Danann.
In addition to its amazing construction, Knowth has a large collection of megalithic art. It accounts for half of the total number of engraved stones in Ireland and one-third of all the megalithic art in Europe. Over 200 decorated stones were found during excavations. Much of the artwork is found on the kerbstones, particularly approaching the entrances to the passages.
Many of the motifs are arcs, spirals, lozenges, crescent shapes and swirling lines. The purpose of the artwork is not known but the carvings are thought to represent the moon, or eclipses of the sun and moon.
Like Newgrange, Knowth is described as a passage tomb, probably due to the fact that cremated human remains were found in the stone basins in the eastern passage. However, more research has revealed that Knowth also has astronomical and calendrical functions. The extensive artwork within the mound seems to represent the sun and the moon. Also, Canadian scientist, Phillip Stooke, has suggested that carvings in the end recess of the eastern cruciform chamber may well be the oldest known representation of the surface of the moon. The carvings on Kerb stone 52 led to it being called ‘The Calendar Stone’. Many believe it represents the cycle of the moon from crescent to full moon. It would have allowed the builders to keep track of moon cycles and ultimately time and seasons.
It was thought for a time that the eastern and western passages were aligned to the sunrises and sunsets at the equinoxes. However, this has been found not to be the case. The setting sun was observed by researchers shining into the western passage on the autumnal equinox, but there was no evidence of sun alignment with the eastern passage.
There seems to be no research into the possibility of alignments with the moon. Given that Knowth has a wealth of what can only be described as lunar or moon symbolism, it would make sense that the ancient builders built this monument to capture the light of the moon in the same way Newgrange takes in sunlight.
Unfortunately, the eastern passage had to be closed, due to structural instability. However, wouldn’t it be wonderful if further research revealed alignments with the moon?
A full-scale excavation of the site undertaken by Professor George Eogan and his team of archaeologists. They discovered a wealth of knowledge that was previously unknown. The entrances to the western and eastern passages were discovered in 1967 and 1968 respectively, and, slowly, the full extent of the magic at Knowth was uncovered. Excavations at Knowth began in June of 1962 and proceeded every year until 2002 when the site was finally opened to the public.
Knowth also has strong connections to An Tuatha de Danann. In ancient times, Knowth was known as ‘Cnogba’ or ‘Cnoc Bui,’ home to the sovereignty goddess, Buí, wife of the sun god Lugh. Bui is said to be buried beneath the mound of Knowth. It is truly a marvellous place full of the mysticism and charm of Ireland’s ancient sites.