Isle of Purbeck

TheIsle of Purbeckis apeninsulainDorset,England. It is bordered by water on three sides: theEnglish Channelto the south and east, where steep cliffs fall to the sea; and by the marshy lands of theRiver FromeandPoole Harbourto the north. Its western boundary is less well defined, with some medieval sources placing it atFlower's BarrowaboveWorbarrow Bay.John Hutchins,author ofThe History and Antiquities of the County of Dorset,defined Purbeck's western boundary as the Luckford Lake stream, which runs south from theFrome.According to writer and broadcasterRalph Wightman,Purbeck "is only an island if you accept the barren heaths betweenArish MellandWarehamas cutting off this corner of Dorset as effectively as the sea. "The most southerly point isSt Alban's Head(archaically St. Aldhelm's Head).

Corfe Castle

From 1974 to 2019, the whole of the Isle of Purbeck lay within the local government district ofPurbeck,which was named after it. The district extended significantly further north and west than the traditional boundary of the Isle of Purbeck along the River Frome. Following the abolition of the district on 1 April 2019, the Isle now lies within theDorsetunitary authority area.

In terms of natural landscape areas, the southern part of the Isle of Purbeck and the coastal strip as far asRingstead Bayin the west, have been designated as National Character Area 136 – South Purbeck byNatural England.To the north are theDorset Heathsand to the west, theWeymouth Lowlands.

Geology

See also:Geology of Dorset

Map of the Isle of Purbeck

The geology of the Isle is complex. It has adiscordant coastlinealong the east andconcordant coastlinealong the south. The northern part isEoceneclay(Barton Beds), including significant deposits ofPurbeck Ball Clay.Where the land rises to the sea there are several parallel strata ofJurassicrocks, includingPortland limestoneand thePurbeck beds.The latter includePurbeck Marble,a particularly hardlimestonethat can be polished (though mineralogically, it is notmarble). A ridge ofCretaceouschalkruns along the peninsula creating thePurbeck Hills,part of theSouthern EnglandChalk Formationthat includesSalisbury Plain,theDorset Downsand theIsle of Wight.The cliffs here are some of the most spectacular in England, and of great geological interest, both for the rock types and variety oflandforms,notablyLulworth CoveandDurdle Door,and the coast is part of theJurassic CoastWorld Heritage Sitebecause of the unique geology.

In the past, quarrying of limestone was particularly concentrated around the western side ofSwanage,the villages ofWorth MatraversandLangton Matravers,and the cliffs along the coast between Swanage andSt. Aldhelm's Head.The "caves" atTilly Whimare former quarries, andDancing Ledge,Seacombe andWinspitare other cliff-edge quarries. Stone was removed from the cliff quarries either by sea, or using horse carts to transport large blocks to Swanage. Many of England's most famouscathedralsare adorned with Purbeck marble, and much ofLondonwas rebuilt in Portland and Purbeck stone after theGreat Fire of London.

By contrast, the principal ball clay workings were in the area betweenCorfe CastleandWareham.Originally the clay was taken bypack horsetowharveson theRiver Fromeand the south side ofPoole Harbour.However, in the first half of the 19th century the pack horses were replaced by horse-drawn tramways.With the coming of the railway from Wareham to Swanage, most ball clay was dispatched by rail, often to the Potteries district ofStaffordshire.

Quarrying still takes place on Purbeck, with bothPurbeck Ball Clayandlimestonesbeing transported from the area by road. There are now no functioning quarries ofPurbeck Marble.ThePurbeck Mineral and Mining Museumdisplays an exhibition about ball clays, mining and the associated narrow gauge railways.

Wild flowers

Ophrys sphegodes,the Early Spider Orchid

The isle has the highest number of species of native and anciently introducedwild flowersof any area of comparable size in Britain.This is largely due to the varied geology. The species most frequently sought is Early Spider Orchid (Ophrys sphegodes), which in Britain, is most common on Purbeck. Nearly 50,000 floweringspikeswere counted in 2009. Late April is the best time, and the largest population is usually in the field to the west ofDancing Ledge.Smaller numbers can be seen on a shorter walk inDurlston Country Park.This orchid is the logo of theDorset Wildlife Trust.Cowslip meadows (Primula verisandPrimula deorum) are at their best shortly afterwards and Durlston Country Park has several large ones.

In early May, several woods have carpets of Wild Garlic (Allium ursinum). King's Wood and Studland Wood, both owned by theNational Trust,are good examples. At around the same time and later some Downs have carpets of yellow Horseshoe Vetch (Hippocrepis comosa) and blue Chalk Milkwort (Polygala calcarea). In late May the field nearOld Harry Rockshas a carpet of yellow Kidney Vetch (Anthyllis vulneraria).

Blue and white flowers ofSheep's bit(Jasione montana) and pink and flowers of Sea Bindweed (Calystegia soldanella) lend colour toStudlanddunes in June. Both Heath Spotted Orchid (Dactylorhiza maculata) and Southern Marsh Orchid (Dactylorhiza praetermissa) are frequent on Corfe Common that month, and Harebells (Campanula rotundifolia) and Purple Betony (Stachys officinalis) flowers add colour to the Common in July.

Dorset Heath (Erica ciliaris), thecounty flower,can be found in July and August in large numbers, especially on and aroundHartland Moor,in damper parts of the heathland. Bog Asphodel (Narthecium ossifragum) gives displays of yellow flowers there in early July. Marsh Gentian (Gentiana pneumonanthe) is found less frequently in similar areas from mid August to mid September.

Human history

A number of Romano-British sites have been discovered and studied on the Isle of Purbeck, including a villa atBucknowle Farmnear Corfe Castle, excavated between 1976 and 1991.The Kimmeridgeshaleof the isle was worked extensively during the Roman period, into jewellery, decorative panels and furniture.

At the extreme southern tip of Purbeck isSt.Aldhelm's Chapel,which is Norman work but built on a pre-Conquest Christian site marked with a circular earthwork and some graves. In 1957, the body of a 13th-century woman was found buried to the north of the chapel, suggesting there may have been a hermitage in the area. In 2000, the whole chapel site was declared a Scheduled Ancient Monument. The precise function of the chapel building is disputed, with suggestions that it may have been a religious retreat, achantryfor the souls of sailors who had drowned off St Aldhelm's Head or even a lighthouse or warning bell to warn sailors.Victorian restorationwork of the chapel found signs that abeaconmay have adorned the roof. The present cross on the roof is Victorian.

The town of Wareham retains its Saxon earth embankment wall and its churches have Saxon origins. One of these, St Martins-on-the-Walls, was built in 1030 and today contains traces of medieval and later wall paintings.

The village of Corfe Castle is named after the castle that overlooks the village, commanding a strategic gap in the Purbeck Ridge. The present castle dates from after the Conquest of 1066 but may have replaced Saxon work, as the village was where Saxon KingEdward the Martyrwas murdered in 978. The supposed location of his murder is traditionally on or near the castle mound. Corfe was one of the first English castles to be built in stone, at a time when earth and timber were the norm. This may have been due to the plentiful supply of good building stone on Purbeck.

SirJohn Bankesbought the castle in 1635 and was the owner during theEnglish Civil War.His wife, LadyMary Bankes,led the defence of the castle when it was twice besieged by Parliamentarian forces. The first siege, in 1643, was unsuccessful, but by 1645 Corfe was one of the last remaining royalist strongholds in southern England and fell to a siege ending in an assault. In March that year Corfe Castle was ' "slighted" (demolished) on Parliament's orders. Owned by the National Trust, the castle is open to the public. It is protected as a Grade I listed building and aScheduled Ancient Monument.

Geography

A large part of the Isle of Purbeck is within theDorset National Landscapearea. A portion of the coast aroundWorbarrow Bayand theghost villageofTynehamis owned by theMinistry of Defence,who have used it as a training area since 1943.Lulworth Rangesare part of the Armoured Fighting Vehicles Gunnery School atLulworth Camp.Tanksand otherarmoured vehiclesare used in this area andshellsare fired. Due to safety reasons, right of entry is only given when the army ranges are not in operation. Large red flags are flown and flashing warning lamps onBindon HillandSt Alban's Headare lit when the ranges are in use. At such times the entrance gates are locked and wardens patrol the area.

Swanage,the main town and resort of Purbeck, with thePurbeck Hillsin the background.

Other places of note are:

• Swanage,at the eastern end of the peninsula, is aseaside resort.At one time it was linked by a branch railway line fromWareham;this was closed in 1972, but has now partially reopened as theSwanage Railway,aheritage railway.
• Studland:This is a seaside village in its own sandy bay. Nearby, lying off-shore from The Foreland (also Handfast Point), are the chalk stacks namedOld Harry Rocks:Old Harry and his Wife.
• Poole Harbouris popular with bird watchers, windsurfers and yachters; it containsBrownsea Island,the site of thefirst-ever Scout camp.
• Corfe Castleis in the centre of the isle, overlookingCorfe Castle village.
• Langton Matravers,which was once the home of several boys'preparatory schools;the last of these,The Old Malthouse School,closed in 2007.
• Kimmeridge Bay,with its fossil-rich Jurassic shale cliffs and the oldest continually working oil well in the UK.
• Worth Matravers:A village of stone houses around a pond, which is a regular feature on postcards of the Isle of Purbeck.

External links

• Purbeck District Council
• Wareham Town Museum
• Map and aerial photo sourcescentred on Corfe Castle atGrid reference:SY 960 820.