LITMIR.BIZ

      Granite is the bedrock of the Isles of Scilly, seen at its best around Peninnis Head (Walk 3)

Location

      The Isles of Scilly lie 45km (28 miles) west of Land’s End: a position that ensures they are omitted from most maps of Britain, or shown only as an inset. There are five inhabited islands and about fifty other areas that local people would call islands, as well as a hundred more rocks, and more again at low water. The islands are not part of Cornwall, perish the thought, but a self-administering unit; you could think of this as the smallest county in Britain (see www.scilly.gov.uk). The total landmass is a mere 16km2 (6¼ square miles). The waters around the Isles of Scilly, extending as far as the 50m (165ft) submarine contour, form a Marine Park of around 125km2 (50 square miles). Despite the small area of the islands, walkers can enjoy up to about 80km (50 miles) of truly remarkable routes around one of Britain’s most charming and intensely interesting landscapes.

Geology

      The geology of the Isles of Scilly can be summed up in one word – granite. The islands are the south-western extremity of a deep-seated granite mass, or batholith, that reaches the surface of the earth around Dartmoor, Bodmin Moor and Land’s End. Granite is the bedrock of the Isles of Scilly, and it breaks down to form a stony, sandy or gritty soil, as well as bright white sandy beaches. In some places around the coast and occasionally inland, the granite forms blocky cliffs and tors, rounded boulders or tilted slabs that have such a rough texture that they provide excellent grip for walkers. In other places chemical weathering of less stable minerals within the granite causes the rock to crumble, or peel away in layers. As a building material, granite has been used for centuries, but only in relatively recent times has it been possible to split the rock into squared blocks more suitable for substantial buildings.

      While the Isles of Scilly escaped the Ice Age that affected much of Britain, it didn’t escape the permafrost conditions that pertained south of the ice sheets, breaking up the granite tors and forming a stony, sandy soil. Nor did the islands fare too well as the ice began to melt and sea levels began to rise. It is thought that Scilly became separated from the rest of Britain around 10,000 years ago. It may well have been a single landmass for a while, but a combination of rising sea levels and coastal erosion produced the current pattern of five islands and a bewildering number of rocks and reefs. Before the arrival of the first settlers, it was no doubt a wild and wooded place.

Ancient History

      Arthurian legend points to the Isles of Scilly as the last remnants of the lost land of Lyonesse; but while a submerged landscape does exist around the islands, it was never Lyonesse. In 1752 the Cornish antiquarian William Borlase discovered and recorded submerged field systems on the tidal flats near Samson. It seems that the first settlers were Neolithic, but a more comprehensive settlement of the islands came in the Bronze Age, up to 4000 years ago. Some splendid ritual standing stones and stoutly constructed burial chambers remain from this time, and excavations have revealed skeletons, cremated remains and a host of artefacts. When the Romans began their occupation of Britain 2000 years ago, criss-crossing the land with straight roads, settlement patterns on the Isles of Scilly were in huddled formations, as witnessed today on Halangy Down and Nornour. No doubt the Romans traded with the islands, as coins have been discovered, but it seems they established no lasting presence. In later centuries the Isles of Scilly attracted Christian hermits, leaving some of the islands blessed with the names of saints. That great seafaring race, the Vikings, also visited the islands. From time to time the Isles of Scilly have been a haven for pirates, their retreat every now and then smashed by the authorities of the day. In the 11th century over one hundred pirates were beheaded in a single day on Tresco!