Archaeologists have established that long barrows were built by pastoralist communities shortly after the introduction of agriculture to Britain from continental Europe.

It consisted of a sub-rectangular earthen tumulus, estimated to have been 15 metres (50 feet) in length, with a chamber built from sarsen megaliths on its eastern end.

Chestnuts Long Barrow is a scheduled ancient monument,[1] standing on private land belonging to a neighbouring house, Rose Alba.

[5] The change came about through contact with continental European societies, although it is unclear to what extent this can be attributed to an influx of migrants or to indigenous Mesolithic Britons adopting agricultural technologies from the continent.

[6] The region of modern Kent would have been key for the arrival of continental European settlers and visitors, because of its position on the estuary of the River Thames and its proximity to the continent.

[9] Environmental data from the vicinity of the White Horse Stone, a putatively prehistoric monolith near the River Medway, supports the idea that the area was still largely forested in the Early Neolithic, covered by a woodland of oak, ash, hazel/alder and Amygdaloideae (stone-fruit trees).

[10] Throughout most of Britain, there is little evidence of cereal or permanent dwellings from this period, leading archaeologists to believe that the island's Early Neolithic economy was largely pastoral, relying on herding cattle, with people living a nomadic or semi-nomadic life.

[15] These chambered tombs were built all along the Western European seaboard during the Early Neolithic, from southeastern Spain up to southern Sweden, taking in most of the British Isles;[16] the architectural tradition was introduced to Britain from continental Europe in the first half of the fourth millennium BC.

[17] Although now all in a ruinous state,[18] at the time of construction the Medway Megaliths would have been some of the largest and most visually imposing Early Neolithic funerary monuments in Britain.

[29] The chambers were constructed from sarsen, a dense, hard, and durable stone that occurs naturally throughout Kent, having formed out of sand from the Eocene epoch.

[38] Alexander thought that they bore closest similarities with long barrows along the Atlantic coast, perhaps imitating those of either Ireland or Brittany.

[44] Around 30 metres (100 feet) west of the long barrow, excavation revealed flints in association with what was interpreted as a Mesolithic hearth.

[64] Along with the human remains were found items probably interred with the dead, such as 34 sherds of ceramic, three stone arrow heads, and a clay pendant.

[66] Excavation found evidence of the northern and eastern edges of the barrow,[67] but all trace of its western and southern ends had been destroyed by levelling and deep ploughing.

[15] Archaeologists have suggested that this is because Early Neolithic Britons adhered to an ancestor cult that venerated the spirits of the dead, believing that they could intercede with the forces of nature for the benefit of their living descendants.

[70] The archaeologist Robin Holgate stressed that rather than simply being tombs, the Medway Megaliths were "communal monuments fulfilling a social function for the communities who built and used them".

[26] Thus, it has been suggested that Early Neolithic people entered into the tombs—which doubled as temples or shrines—to perform rituals honouring the dead and requesting their assistance.

[73] The archaeologist Caroline Malone noted that the tombs would have served as one of various landscape markers that conveyed information on "territory, political allegiance, ownership, and ancestors".

[80] Excavation of this hut uncovered 750 ceramic sherds, charcoal, iron nails, burnt clay, bone, and flint fragments.

[82] Evidence for human activity near the barrow from the 11th through to the 13th century—during the Middle Ages—appeared in the form of 200 ceramic sherds, two hones, and 17 fragments of daub found by archaeologists in the topsoil.

[86] At some point after they had fallen, the inner pair of the chamber's tall stones were further damaged, likely in a process involving heating them with fire and then casting cold water onto them, resulting in breakage.

[89] Supporting this idea is comparative evidence, with the Close Roll of 1237 ordering the opening of barrows on the Isle of Wight in search for treasure, a practice which may have spread to Kent around the same time.

[90] Alexander believed that the destruction may have been brought about by a special commissioner, highlighting that the "expertness and thoroughness of the robbery" would have required more resources than a local community could muster.

[86] Alexander suggested that this evidence confirmed local accounts that Chestnuts Long Barrow had been used as a popular spot for picnics.

[1] In a 1946 paper published in the Folklore journal, John H. Evans recorded a Kentish folk belief which had been widespread "up to the last generation".

[94] Later records reveal that the folk story had gained widespread distribution in England and single occurrences in both Wales and Ireland.

[97] The earliest possible reference to the monuments was provided by the antiquarian John Harris in an ambiguous comment in his History of Kent in Five Parts, published in 1719.

[98] In 1773, the site was described in print by the antiquarian Josiah Colebrooke in a short article for Archaeologia, the journal of the Society of Antiquaries of London.

[4] In the latter part of the 1950s, with plans afoot to build a house adjacent to Chestnuts Long Barrow, the Inspectorate of Ancient Monuments initiated an excavation of the site under the directorship of John Alexander.

[107] Alexander's subsequent excavation report was described by Ashbee as "comprehensive" and "a model of its kind",[104] and by Jessup as "a notable example of modern archaeology in the field".