Opening out into the Irish Sea, the Solway Firth is located on the southwest coast of Scotland where it forms a border between it and England. It is fed from the north by numerous rivers including the Nith, the Annan, the Urr Water, the Lochar Water, and, in England, the River Eden and Liddel Water. One of the least industrialised and most natural large estuaries in Europe, the Solway Firth comprises a range of coastal and marine habitats including saltmarshes, mudflats and sandflats. It contains the third largest area of continuous littoral mudflats and sandflats in the UK. The ever changing pattern of channels and mudflats, coupled with the moderately strong tidal currents, can be dangerous.