Causey Bank Mires is a Site of Special Scientific Interest

Site of Special Scientific Interest

A Site of Special Scientific Interest is a conservation designation denoting a protected area in the United Kingdom. SSSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in Great Britain are based upon...

 in the Derwentside

Derwentside

Derwentside was, from 1974 to 2009, a local government district in County Durham, England.The district took its name from the River Derwent, which made up part of the northern border of the district. Its main towns were Consett and Stanley, with the district council offices on Consett's Medomsley...

 district of County Durham

County Durham

County Durham is a ceremonial county and unitary district in north east England. The county town is Durham. The largest settlement in the ceremonial county is the town of Darlington...

, England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

. It lies alongside and to the west of the Tanfield Railway

Tanfield Railway

The Tanfield Railway is a standard gauge heritage railway in Gateshead and County Durham, England. Running on part of a former colliery wooden wagonway, later a steam railway, it operates preserved steam and diesel industrial tank locomotives. The railway operates a passenger service on Sundays all...

, just under 1 km north of the Causey Arch

Causey Arch

The Causey Arch is a bridge near Stanley in County Durham. It is the world’s oldest surviving railway bridge.It was built in 1725-26 by stonemason Ralph Wood, funded by a conglomeration of coal-owners known as the "'Grand Allies'" at a cost of £12,000...

.

The site consists of a series of flushes with scrub, surrounded by acid and neutral grassland, a habitat with a restricted distribution in County Durham. A number of locally rare plant species are found in the area, including globe-flower, Trollius europaeus.