In article , Basil Jet
writes
I think some were also lost at Triangle sidings and Hammersmith.
I didn't realise trains were lost in the Triangle as well as ships and
planes.
They lost a Circle Line train for a week once.
They found it in Rickmansworth sidings.

I'm told that, when trains full of scrap went into scrapyards, not all
the wagons managed to come back out.

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Clive D.W. Feather