Is this connected with the exploits of the then Mr Winston Churchill when he was captured by the Boers during the Anglo-Boer War in 1899ish?
You're right -- and 1899 was indeed the year. I was referring in particular, to the film
Young Winston, the majority of which deals with his capture by the Boers and subsequent escape. (My Post #8911 stuff about "geological, etc." was a laboured attempt to telegraph "win-stone-church-hill"

)
If my memory serves me correctly, he was on an armoured train (hauled by an 0-4-2T locomotive?) which was ambushed and crashed. He was captured and was taken to somewhere which has the name of the service station - although I don't know what that is.
The armoured-train episode in the film takes place in a rural and hilly part of South Wales (around Coelbren Junction and Craig-y-Nos, on a then still extant remnant of the Neath & Brecon line), standing in for the South African veldt: the confected "armoured train" 's motive power is preserved ex-GW 0-4-2T 1466.
I agree but cant think of the service station either.
The service-station name: the original armoured-train-and-capture incident took place near the station named Chieveley -- in Kwa-Zulu-Natal, on the Durban -- Johannesburg main line. There's also a village in Berkshire, near Newbury, callled Chieveley (I gather that the S.A. Chieveley probably takes its name from the Berkshire one by devious ways, but it's not a certainty). The Berkshire Chieveley also gives its name to a nearby services area at intersection of M4 and A34.
Just looked up the film and was surprised to see Longmoor Military Railway was also used in the filming which I thought was already closed down and largely gone by 1972
Per my best understanding, the LMR sequence in the film is very brief -- involving the freight train on which Churchill stowed away, and rode on out of the Transvaal, into Portuguese territory. Freight train's motive power in film, struck me as a large, modern, and very un-1899-looking loco -- David Shepherd's
Black Prince, or so I may have heard...? Film actually released in 1972; LMR had been disused since 1969 -- some track still un-lifted and usable, when the sequence was shot.
@EbbwJunction1 : you posted first by an hour-and-some; got it right about Churchill and armoured train, but didn't mention the film -- basically the crux of my question --
@Graham H, you were specific re the film's involvement. Could I possibly request you two gentlemen to come to an arrangement, as to which of you takes the floor?