Knowth ( / ˈ n aʊ θ / ; Irish : Cnóbha ) is a very old tomb located near the River Boyne in County Meath, Ireland. It has a large passage tomb and is surrounded by 17 smaller tombs. These structures were built during the Neolithic period, about 3200 BC. Knowth is famous for having the largest collection of megalithic art in Europe. It is part of the Brú na Bóinne complex, a World Heritage Site that also includes the similar passage tombs of Newgrange and Dowth.
After it was first used, Knowth slowly fell into ruin. However, the area remained important for rituals during the Bronze Age. In the early Middle Ages, a royal home was built on top of the large mound. This became the home of the Kings of Knowth or Northern Brega. From the 1960s to the 1980s, archaeologist George Eogan studied the site in detail. Some parts of the monument were rebuilt during this time.
Description
The large mound dates back to around 3200 BC. It is approximately 12 meters (40 feet) high and 67 meters (220 feet) wide, covering about one hectare. The mound has two passages aligned east to west and is surrounded by 127 kerbstones, three of which are missing and four that are damaged. Each passage leads to its own separate burial chamber. The eastern passage leads to a chamber shaped like a cross, similar to one found at Newgrange. This chamber has three recesses and basin stones where the cremated remains of the dead were placed. The right-hand recess is larger and has more detailed megalithic art than the others, which is common for Irish passage graves of this type. The western passage ends in a chamber that is not clearly divided from the passage by a sill stone. This chamber also had a basin stone, which was later removed and is now located about two-thirds along the passageway.
Knowth contains more than a third of all megalithic art found in Western Europe. Over 200 decorated stones were discovered during excavations. Much of the artwork is abstract and is found on the kerbstones, especially near the entrances to the passages. Common motifs include spirals, lozenges, and serpent-like shapes. However, Knowth also has unique images, such as crescent shapes and the oldest known drawing of the moon in history. Some of the art was carved on the back of the stones, a type called "hidden art." This has led to many theories about the purpose of megalithic art in the Neolithic communities that built the monuments in the Boyne Valley. It is possible the art was meant to be hidden, or that the stones were reused from earlier structures.
The east-west orientation of the passages at Knowth suggests they may have been aligned with the equinoxes. However, the original alignment is not clear today. This is because later settlers damaged or altered the passages, and a concrete wall was built in the west entrance during excavations starting in 1962, which limits further study. It is likely the passages were intended to align with the equinoxes. Additionally, changes in Earth's orbit over time, known as Milankovitch cycles, can affect the alignment of ancient monuments. The most detailed research on the alignment and astronomy at Knowth was conducted by researcher Martin Brennan.
History
There is some evidence of human activity during the late Neolithic and Bronze Age periods at the site. Much of this evidence comes from a grooved ware timber circle located near the entrance to the eastern passage. Archaeological findings suggest this area was used for rituals or sacred purposes after the large mound at Knowth had fallen into disuse. Signs of ritual activity include many votive offerings found near the timbers that formed the circle. The hill at Knowth became damaged over time, and the mound or cairn shifted, covering the entrances to both passages. The site was not used for a long time, about two thousand years. Later, it was briefly used as a burial site, with about 35 cist graves discovered during excavations.
During the late Iron Age and early Christian period, the site became a hill fort with ditches and souterrains added. Knowth became a place where people lived for the first time. Two ditches were dug: one at the base of the mound behind the kerbstones, and another at the top. At this time, the entrances to both passages were likely discovered. Evidence includes early Christian graffiti carved on stones in the eastern chamber and four names written in ogham script. It appears that the basin stone from the western chamber was moved in an attempt to remove it but was abandoned in the passage when it became stuck. Knowth became an important political center and the capital of the Kingdom of Northern Brega.
The site was called Cnogba in Old Irish, though its meaning is unknown. This name later changed to Cnoghbha and eventually became Cnóbha in modern Irish. In the medieval Triads of Ireland, Úam Chnogba ("caves of Knowth"), Úam Slángæ (likely Rathcoran), and Dearc Fearna (likely Dunmore Cave) are listed as "the three darkest places in Ireland."
After a short period of military use following the Norman invasion of Ireland, when the Normans built a motte at Knowth in the 12th century, the site was owned by the Cistercian monks of Mellifont Abbey. The mound was again used as a grange or farm, with stone walls built over it and stone buildings constructed within the walls. After the monasteries were dissolved, the site was primarily used for farming until most of it was taken over by the state in 1939.
Archaeological investigation and restoration
In 1941, a short dig at the site was done by Macallister. However, the first detailed study and excavation of Knowth began in 1962, led by George Eogan from University College Dublin. At the start of Eogan’s work, little was known about the full size of the site. The entrances to the western and eastern passages were found in 1967 and 1968, and over time, layers of human activity at Knowth were uncovered. The excavation led to many books and reports about the discoveries. After the dig, conservation, restoration, and rebuilding efforts were carried out.
A layer of white quartz stones was found at the entrances to the large mound. The same was found at Newgrange’s entrance, and archaeologists there believed the stones formed a white front or covering on the monument that had fallen. This white quartz front was rebuilt at Newgrange. However, George Eogan thought Neolithic people could not have built such a covering without it collapsing. He suggested most or all of the white quartz was spread on the ground and left there at Knowth. Some archaeologists supported this choice, but others, like Robert Hensey and Elizabeth Shee Twohig in their paper "Facing the cairn at Newgrange" (2017), argued that both Knowth and Newgrange had white quartz façades. They noted the quartz layers at both sites were thickest near the kerbstones, suggesting the stones slid down the mound rather than being laid flat. They also argued that if builders transported the quartz far, they likely used it as a striking façade, not left it on the ground where it would not be visible. Along with Carleton Jones, Hensey and Twohig pointed out that passage tombs in Brittany, such as Gavrinis and Barnenez, have similar near-vertical dry stone fronts.
Access
The site is located nine kilometers west of Drogheda. Only guided tours are allowed to visit the area. Tours start at the Brú na Bóinne Visitor Centre in Donore. Visitors may view the eastern passage and explore a nearby modern room with information about the site.