The remaining tunnel only has a useful function in terms of easily accessing the track and some trackside equipment boxes in the short area between old and new Thameslink platforms. If it wasn’t already there I don’t suppose it would be built specially. The corresponding down track, the Hotel Curve, was obliterated by the LU and NR works for the various western ticket hall levels.
The curve at 2.42, was called Maiden Lane curve, for going
West towards Paddington, but previous discussions and sources I’ve downloaded a few years ago suggest it might never have actually had track laid. There was no equivalent to it in the other direction.
AIUI the attachment in this post of mine from 2011 shows the situation in 1863, the 1962 texts from Railway Magazine reckon it had been filled in by 1868:
This one of the old tunnels from Kings Cross to Moorgate,you can access these tunnels off York way, when were they closed?. And they would come in useful now, as they would be doing to same thing as the new Canal Tunnels at St Pancras International
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