Boltar wrote:
From google earth there seems to be a single track line that runs past
Drayton Park station on the east side at a higher level than the
moorgate line then disappears into its own tunnel further south. What
line is this?

The Canonbury Curve, which connects Finsbury Park and the ECML to the
North London Line. It currently has no passenger service, though it is
used by freight and possibly some empty coaching stock.

There was a plan to use it to terminate the East London Line extension
at Finsbury Park (rather than H&I), but that would require 8 train
movements an hour on the flat across the entire NLL formation, so was
unsurprisingly dropped as a non-starter.

U

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