The Solway Viaduct begins at OS Grid Reference NY212628.

IT WAS low tide as we stood looking across the Solway Firth. Wet sand stretched into the distance. A mile away lay the coast of Scotland.

'If you squint a bit, it's almost possible to imagine you could walk right across to the other side,' I said.

My assistant squinted, but said nothing.

'This must be where Sir James Brunlees stood when he planned his railway,' I continued. 'Think of it: a viaduct stretching from here to there. And now there's nothing.'

The tide turned. We watched the waters come surging back. Suddenly there were men entering the water and setting off towards the other side. 'What are those men doing? Stop them]' I ordered, but my assistant was unmoved.

'They know what they're doing,' he said. 'They're haaf-netting for salmon.' They waded into the tide and set up their haaf-nets. Then they waited, and we watched.

And that was it . . . nothing else. These men solemnly leaning on their nets was the only sign of human activity in the Solway. Not even a boat today. Definitely no trains.

A hundred years ago you could catch a train here to take you across the water to Scotland. The Solway Junction Railway, it was called. In 1866 they built a viaduct 1,950 yards long to carry the trains that ferried ore from Cumberland to the iron works of Lanarkshire.

It stood on cast-iron columns driven into the seabed by a steam-powered pile-driver. There were sea embankments at each end, 154 yards to the north and 440 yards to the south.

The trains ran back and forth, carrying passengers too, until the freezing winter of 1880-81. The thaw brought huge blocks of ice floating down the Firth. Part of the viaduct was smashed away and the Solway Junction Railway was doomed. Seriously weakened, the entire structure eventually had to be demolished.

All that remains is the sea embankment where we stood: great blocks of sandstone marching sadly into the water. I tried without success to imagine the whistle of a passing train.