Herod,
At a guess, Ballykelly, where the Belfast - Stroke City (Londonderry) main line crossed the main drag several hundred feet up from the threshold. My Vigilant school, 664VGS, used to hold summer camps there when we were based at Belfast City (BHD) where I noticed that the runway had been shortened to bring the threshold inside of the railway line and which was heavily fenced off with razor wire and other security devices.
Our operation there sometimes caused a bit of confusion for those operating into Eglinton airfield about five miles to the west, which was at the time trying to get itself sorted out as a regional hub and had one or two Ryanair flights a day. Teaching circuits to a student one day and listening out on the Eglinton tower frequency, I heard the controller warn an inbound Ryanair flight that "Ballykelly is active and there is traffic downwind for 26" the pilot asked Eglinton "Where is BallyKelly?" and before the controller could answer I just said on the radio "Look out your left window" as an Airbus or a 737 sailed past us sliding down the ILS.
And, of course, in 2006 there was the EirJet Airbus, the crew of which, due I believe to a lack of appropriate nav plates/maps or whatever, landed on R/W 26 and much to the surprise of the crew and passengers was almost immediately surrounded by green land rovers and people in camouflage fatigues who were pointing guns at them. Oooops.
Oh, and talking of apocryphal, I did hear that it all depended as to who pressed the right button first, signalman/controller as to whether the train got right of way or the traffic on finals.