Jan. 17, 2007 - Inquiry into the geospatial relationships of the Thornborough Henges (to each other and to other Neolithic monuments in the greater viewscape and surrounding landscape) evidences a large regional pattern of monument placement and knowledge of the true scale of the earth. Additional evidence implies accurate astronomy and heliocentric understanding of celestial motions. Results are discussed in greater detail below, after description of the major monuments considered in the study. Study is ongoing and updates follow below.

Google Earth Placemarks kmz file: neolihic_calc.kmz

Oct. 12, 2006 - Thornborough Henges are foci in the struggle to defend and preserve ancient sites and their environs from destructive modern developments. Quarrying at Thornborough has already destroyed adjacent areas to the west and north of the henges, and quarry expansion is again sought. Because the immediate landscape around the Thornborough Henges remains threatened, I've renewed focus on the Ure-Swale Neolithic monuments, acquired more accurate coordinate data, and expanded study with additional monuments.

The large henges on the Vale along the Ure and Swale Rivers were included in my preliminary study, The Possible Geodetic Properties and Relationships of Neolithic Monuments of the British Isles (2000). Herein, I describe the complex of late Neolithic henges and related placemarks and discuss their geodetic relationships and new findings. A previous page, neolithic.html, provides additional introductory materials as do my Archaeogeodesy pages.

Among the Late Neolithic henges constructed about five millennia ago, the complex of the three large henges at Thornborough is pre-eminent. The immediate environs destroyed by quarrying are dark shaded.

Sites Considered

Thornborough Henges. Between Thornborough, Nosterfield, and East Tanfield, a complex of three late Neolithic/early Bronze Age, almost identical, Class IIa henge monuments (an embankment between two ditches) form a mile-long, approximate alignment roughly northwest to southeast. As part of the Thornborough Henges NMP project, the henges were surveyed at 1/2,500, and the features mapped. The henges are sub-circular enclosures, with two opposed entrances. Details of the infilled ditches are visible as cropmarks and/or shallow earthworks. Excavations identified phased construction, the outer ditches with an external bank were constructed first while the larger, more-impressive inner bank and ditch is a second phase. Excavation revealed white, gypsum-covered banks. Thornborough Centre's inner ditch measured 17.7 m wide and up to 2.1 m deep, similar to the dimensions of the North and South henges, and the up-to-18m-wide banks were deliberately leveled along the outer boundary. Cursuses, pit alignments, post moulds, and burial sites accompany the henges.

• Thornborough North is situated in dense woods and remains best preserved.
• Thornborough Centre has the highest embankment, reaching to near 5 m. The widest external diameter is 238 m. The inner ditch has squared terminals. The outer ditch is segmented and narrower. The two entrances, located to the northwest and southeast, are not perfectly aligned. The cursus is visible within the overlain earthwork. Aerial image.
• Thornborough South is most damaged, by agriculture and bulldozing. A 350 m long double pit alignment was discovered near to and west of the henge. Aerial image.

Hutton Moor Henge, with an external diameter circa 240-254 m, represents one of the largest of henges, and the largest in the region. The 45 m wide embankment, with entrances at bearing 172 and 348°, is 173 m across, and remains to 3 m high. As at Thornborough, the ditch terminals were squared at the entrances. While quite reduced and denuded by agricultural tillage, the inner ditch, visible as a slight depression 5 m wide, was circa 10-18 metres wide with a 93-96 m internal diameter range. The wide external ditch was traced around the entire earthwork except at the entrances.

Nunwick Henge is situated on the axis of Thornborough North and Centre. Nunwick was located on aerial photographs and, while reduced and denuded by modern ploughing, remains visible as a cropmark with two opposed north and south entrances, bearings 129° and 350° from north. A shallow internal ditch and low bank remain with a slight, wide, traceable external depression up to 210 m in diameter. Excavation in 1961 by D. P. Dymond determined the bank was 18 m wide and the ditch was 14 m wide and 1.80 m deep with a 9 m wide berm between the bank and ditch.

Cana Barn Henge, much reduced and obliterated by cultivation, is visible as cropmarks. The earthwork has a ditch and outer bank up to 174 m wide with opposing entrances 40 m wide at 169 and 354° from north. Soilmarks on aerial photographs indicate internal features. Both the Hutton Moor and Cana Barn henges are located on a ridge.

File thornborough.xls has an additional scatterplot. Placemarks thornborough.kmz.

Tenlands Henge is about 58 m wide and survives as a cropmark near Cana Barn Henge.

Devil's Arrows Stone Row at Boroughbridge currently consists of three immense, standing stones, 6.9, 6.7, and 5.5 m tall and 5.5 to 6.7 m in circumference. Only one menhir in the British Isles is taller; 7.8 m Rudston Monolith is located due east, at 0.634 degrees arc distance. The Devil's Arrows form a 174 m long, approximately-straight line on an axis 26 degrees west of north. In 1538, Leland described a fourth center stone, with the center menhirs only six to eight feet apart. Alternate names include the Devil's Bolts, the Three Greyhounds, and the Three Sisters.

Castle Dykes Henge is a well-preserved oval bank to 82 m in diameter, over 1 m high and 9 m wide, with an internal ditch 10 m wide and 1 m deep. An eastern entrance faces the highest viewpoint. The earthwork is situated on a hill spur, about 30 km WNW of Thornborough.

Yarnbury Henge consists of a rock-cut ditch 3 m wide and 0.50 m deep, and an external bank of turf-covered stones up to 35 m in diameter, 0.50 m high and 4 m wide. Near the entrance (on the south-east) a 10 m section of the bank and ditch were destroyed by recent quarrying. The henge is situated on a slight rise, about 30 km SW of Thornborough.

Newton Kyme Henge is visible as cropmarks and survives as a slight earthwork. The henge, a sub-oval enclosure with three ditchs and a 1 m bank between the inner and middle ditches, has a maximum diameter near 250 m. The inner ditch has opposed entrances at 170 and 350 degrees, while the middle and outer ditches are irregular and segmented. Ground survey in 1979 reported a wide, oval inner ditch visible as a slight hollow and widely separated from the outer ditches (ditch diameters about 210, 180 and 90 m). The Class IIA henge has close parallels with the regional group of Late Neolithic/Early Bronze Age Yorkshire henges. Newton Kyme is south of Devil's Arrows over 20 km.

Ferrybridge Henge has the typical circular bank with concentric inner and outer ditches. Ferrybridge Henge overlays smaller circular monuments—hengi-form monuments and circles of possible post pits—dated between 3500- 3000 BCE. This southernmost of the Yorkshire henges is located about 58 km SSE of Thornborough Henges.

Catterick Henge was lost to quarrying. A pit cluster was closely associated with the henge. A 38 m wide cairn incorporated into the embankment may predate the henge monument.

Thornborough Cursus, visible as a cropmark, is overlain by the southern sections of Thornborough Centre and is visible between the ditch and bank. The rounded south-west end and most of the monument west of the henge was destroyed by gravel quarrying, during which a stone burial cist was discovered . Excavations were undertaken in the 1940s and 1950s. No north-eastern terminus was determined. The 44-55 m wide cursus runs roughly NE-SW for a known length near 1200 m. Fill from the up to 3 m wide by 1 m deep ditches was banked on the inner sides. OSGB Grid Reference SE 2808 7899 to SE 2884 7958.

Scorton Cursus destroyed by gravel quarrying.

Initial findings widened the area under study. Some of the more distant sites are not yet described here, such as Hastings Hill and West Agra. Site coordinates follow below.