“Hide them in caves and cellars, but not one picture shall leave this island”
Winston Churchill, 1940
“Cuddiwch nhw mewn ogofâu neu selerau ar bob cyfrif, ond ni fydd yr un llun yn gadael yr ynys hon”
Winston Churchill, 1940
During the Second World War, The National Gallery faced an urgent challenge: how to protect its priceless collection from the escalating threat of bombing in London. In 1939, thousands of paintings were quietly transported from Trafalgar Square to a network of stately homes across Wales and Gloucestershire. But these dispersed locations soon proved unsuitable, lacking stable environmental conditions and becoming vulnerable targets. Following Winston Churchill’s famous directive — the search began for a secure subterranean refuge.
Yn ystod yr Ail Ryfel Byd, roedd her fawr yn wynebu’r Oriel Genedlaethol: sut i ddiogelu ei chasgliad amhrisiadwy rhag y bygythiad cynyddol o fomio yn Llundain. Yn 1939, cafodd miloedd o baentiadau eu cludo’n dawel o Sgwâr Trafalgar i rwydwaith o blastai ledled Cymru a Swydd Gaerloyw. Ond buan iawn y daeth pobl i sylwi bod y lleoliadau hyn yn anaddas, am eu bod heb amodau amgylcheddol sefydlog ac yn dod yn dargedau. Yn dilyn cyfarwyddiadau enwog Winston Churchill — dechreuodd y gwaith o chwilio am loches danddaearol ddiogel.
Manod Quarry, a slate mine near Blaenau Ffestiniog, North Wales, was chosen for its vast underground caverns, stable temperatures, and remote location. By 1941, five brick‑built, air‑conditioned storage buildings had been constructed inside the caverns, alongside an above-ground conservation studio. In an extraordinary logistical operation, more than 2,200 paintings were transported to the quarry, including Van Dyck’s Equestrian Portrait of Charles I — whose crate was so large the road had to be lowered beneath the bridge leading up to the quarry to allow passage.
Remarkably, the paintings returned to London after the war in better condition than when they left, with the lessons learned at Manod helping shape modern conservation practice worldwide.
Dewiswyd Chwarel Manod, chwarel lechi ger Blaenau Ffestiniog, gogledd Cymru, oherwydd bod ganddi geudyllau tanddaearol enfawr a thymheredd sefydlog, ac am ei bod mewn lleoliad anghysbell. Erbyn 1941, roedd pum adeilad brics gyda system awyru wedi’u hadeiladu yn y ceudyllau i storio’r paentiadau, yn ogystal â stiwdio gadwraeth uwch ben y ddaear. Mewn gwaith logistaidd eithriadol, cludwyd dros 2,200 o baentiadau i’r chwarel, gan gynnwys Portread Marchogol Van Dyck o Charles I — roedd crât y llun mor fawr bu’n rhaid gostwng y ffordd o dan y bont a oedd yn arwain at y chwarel er mwyn cael mynediad.
Yn rhyfeddol, aeth y paentiadau yn ôl i Lundain ar ôl y rhyfel mewn cyflwr gwell na phan wnaethant adael, a bu i’r gwersi a ddysgwyd yn Chwarel Manod helpu i ddylanwadu ar arferion cadwraeth modern ledled y byd.
Eighty years later, the site survives only as a fragile, rapidly deteriorating time capsule. Access is now unsafe, but Cotswold Archaeology, working with Cadw, Welsh Slate, the Crown Estate and The National Gallery, was granted special permission to record the quarry before it became inaccessible for good. The team created a detailed building survey, captured oral histories from local miners, and developed a 3D digital reconstruction forming part of a new interactive StoryMap. This resource brings together historic photographs, wartime footage, modern survey data and GoPro film to reveal Manod’s hidden history in vivid detail.
Wyth deg mlynedd yn ddiweddarach, mae’r safle’n gapsiwl amser bregus sy’n dirywio’n gyflym. Ar hyn o bryd, nid yw’n ddiogel i fynd i’r chwarel, ond drwy weithio gyda Cadw, Welsh Slate, Ystad y Goron a’r Oriel Genedlaethol, cafodd Cotswold Archaeology ganiatâd arbennig i recordio’r chwarel cyn iddi fynd yn amhosibl cael mynediad ati. Mae’r tîm wedi creu arolwg adeilad manwl, gan gasglu hanesion llafar gan lowyr lleol a datblygu adluniadau digidol 3D i ffurfio rhan o Fap Stori rhyngweithiol newydd. Mae’r adnodd hwn yn dwyn ynghyd ffotograffau hanesyddol, deunydd o gyfnod y rhyfel, data arolwg modern a ffilm GoPro i ddatgelu hanes cudd Manod yn fanwl.
