Treftadaeth Conference

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Llangors Lake Crannog Investigation and
Conservation
Treftadaeth Conference 2nd July 2009
Dr Sian Rees Inspector of Ancient Monuments
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1. Llangors Lake Crannog Conservation
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Llangors Lake, near Talgarth, Brecknock - the
largest natural lake in Wales
Crannog - artificial island constructed for
settlement. Found Scotland and Ireland
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A unique Site in Wales - Wales's only Crannog
Discovered 1870 by Edgar and Henry Dumbleton
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Scheduled Ancient Monument, SSSI and SAC
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2. Llangors Lake Crannog Discovery
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Dumbleton's Excavations showed plan and
construction
Composed of boulders on brushwood and timber base
over shell marl
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Rings of upright timber palisades bounded site
Linked by causeway to shore
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Log boat found nearby in 1925, C14 dated to 10thC
AD
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3. Llangors Lake Crannog Finds
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Early medieval shrine mount c. 9th century
High status site built by kings of Brycheiniog in
9thC
Fine metal artefacts - brooch terminal, reliquary
strap hinge
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Finds suggest important settlement with political
and religious links
High quality textiles with embroidered designs
Animal bones and worked timbers
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4. Llangors Lake Crannog History
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Llandaff Charters suggest royal palace at
Llangors in 8th C
Early monastery - 3 Christian crosses, circular
churchyard St Paulinus
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Royal Brycheiniog kings (Awst and Tewdwr) gave
estate of Llan Cors to Bishops Euddgwy and Libiau.
Anglo-Saxon Chronicles AD 916 Aethelflaed, Lady
of Mercia sent army in reprisal for murder of
Abbott Ecgberht.
Mercian army destroyed Brecenamere (crannog)
captured queen and 33 others
Probably king was Tewdwr ap Elised, King of
Brycheiniog
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5. Llangors Lake Crannog Erosion
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Surveys of 2004, 1987 and 1870 showed extent of
erosion
Original D-shaped island had been extended -
several timber rings
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Wave action exposing rings of timbers on W
vulnerable to breakage
Cadw funded erosion control programme designed by
Giffords
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MARC did further underwater excavation
Dredged material sieved - whetstones, drinking
horn terminal, bracelet
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6. Llangors Lake Crannog Engineering Solution
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Lagoon between elements still and would silt
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7. Llangors Lake Crannog Engineering Project
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Historic timbers marked
Place geotextile on lake bed - cut around timbers
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Place sand bags around timbers
Rock bund and armour positioned
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Stone infill positioned
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8. Llangors Lake Crannog Archaeological
Protection
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Carefully designed to avoid damage to archaeology
Materials moved from temporary floating jetty
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Transportation by flat bottomed barges.
Archaeological watching brief throughout.
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Archaeologists guided positioning of stone and
rock.
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9 Llangors Lake Crannog The Aftermath
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Lake levels dropped during project - difficult
for pontoon
Weather terrible - February - and ice formed on
lake
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Solution appears to have worked - stable shoreline
Periodically checked to ensure no modification
required.
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Interpretation provided by new 'Crannog'
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Treftadaeth Conference 2nd July 2009
Llangors Lake Crannog Investigation and
Conservation
Dr Sian Rees Inspector of Ancient
Monuments