A grey heron stands still in the estuary, waiting for a catch. Behind it the railway viaduct stretches out. The heron turns its head but, otherwise, is not disturbed by the rattle of the passenger train travelling north. At the edge of the water, a pair of redshanks skittle manically across the mudflat, seeking out worms and shellfish left behind by the outgoing tide.
This is dangerous ground. The coastguard office's warnings are clear: fast rising tides, quicksands and hidden channels. Faster currents disturb the slower moving tide as it tracks towards the sea. The Kent Estuary, like Morecambe bay where the river meets the sea can, as the Chinese cockle pickers tragically discovered, prove lethal.
The autumn light begins to fade over the Lakeland hills and the green, lowland meadows. The long, flat stretch of treacherous mud reveals ever more of itself as the tide continues to recede.
It's getting colder and I'm glad to board the train. A few miles down the line, we pass through Carnforth Railway Station. With its rescued clock and refurbished refreshment bar, it's become a heritage memorial to the British Film Industry. This is the station where David Lean directed Noel Coward's Brief Encounter, voted second in a poll to discover Britain's most romantic movie. It starred Celia Johnson and Trevor Howard, all clipped vowels and crisp consonants. Not quite what you'd expect in this northern outpost. All that repressed emotion and need to do the right thing, I reckon that would have gone down well enough up here, though.