Seems I'm none too bright with the multi-quoting routine: I'll just reply to posts in order.
krus_aragon: whimsical territory aside -- though the country has had a modicum of narrow gauge (very little, if any, now remains); it is and has been always strongly predominantly, what by all normally observed conventions is definitely not-narrow-gauge.
Cowley: not UK -- as stated in my original question, the country which had this distinction as at 60 years ago is one which greatly surprised me, and which I'd not have thought of in this connection, in a million years.
A Challenge: I think I see your logic here; but it isn't Liechtenstein.