Portland Island, Dorset World Heritage Coast

Portland Island, Dorset World Heritage Coast

Portland is actually an island, connected to the mainland by Chesil Beach. Quarrying has created a heritage associated with the stone and a landscape that contains beautiful and rare wildlife.

The Island is connected to the mainland by a single road from Wyke Regis and Weymouth. You can get to the island by bus, walk down the Merchants Railway and get a boat from Weymouth.

135 million years ago limestone formed in a shallow sea near the end of the Jurassic Period. The limestone rock is composed from minute structures called ooliths which formed around grains of sand or shell fragments that were on the shallow sea floor. This action built up layer upon layer of limestone.

Portland Stone has an even structure and can be cut or sculpted in any direction. This pliability, plus its hardness, colour and durability, makes Portland limestone particularly suitable as a building stone. Quarrying for Portland Stone took off in the 17th Century when Christopher Wren specified the stone to rebuild St Paul's Cathedral after the great fire of London in 1666. The stone was quarried from the East Weares landslides.

Later, quarrying moved to the top of the Island where the stone was worked along the natural fracture using only hand tools. Quarries like Tout and Kingbarrow consist of dry stone walls and rock faces, tracks and alley ways. In places railway lines lead to the cliff tops where waste rock was just tipped over the edge onto the sea. Other old railway lines link up with the Merchant's Railway and run down a steep incline to the harbour.

When steam and later hydraulic machinery arrived, many of the old areas were re worked for the stone. The result is a more open landscape with piles of massive stone.

Today stone is still removed in a traditional fashion, using black powder to loosen the rock that lies between the gullies. However waste rock is either crushed for aggregate or is dumped in backfill. The result is a very different quarry landscape of large, open sites with little interest.

Before the railway existed, the raw stone was exported without being worked, as the journey could well have damaged any masonry work. Once the railway arrived, masonry companies established themselves on the Island and three survive today. Hanson Bath and Portland Stone use the largest circular saws in Europe, which are a 3.5 metres across. At the masonry works, the squared blocks are sawn into slabs by these huge circular saws. Secondary saws then cut the slabs into the full range of masonry. Some ornamental pieces are still worked by hand. The stone is then loaded onto lorries and taken to the building site.

In the past there was little restoration of the quarry sites after they were finished with. Today the industry is required to restore any abandoned quarries.

Devon and Dorset World Heritage Coast