Many thanks to all – very helpful. It was certainly an odd looking machine.
OG

Longshot – You are quite correct. I meant to say Dublin-London and put Rome again 😮

Although the airport is more or less decided as Ciampino, I was looking at some other photos of the same trip and I was wondering if anyone could identify the airline for the DC-3 in the background of this shot. It is just under the wing of the Connie and it has fairly distinctive tail markings.

Longshot – you are right when you say Kano was not on the route to South America. The airlines and aircraft that came through Kano were either on their way to Lagos and sometimes Accra or going directly South towards the Congo and South Africa. I don’t know what KLM were flying in those days but they have had a long time presence at Kano and I think they still fly there now. It could have been as you say a Shell charter as it seems a small aircraft to be flying such a long route from Amsterdam.

Maybe a wild guess:
The name “Saint Nevin” or Kevin directed my search to
http://1000aircraftphotos.com/Contributions/McKillop/6083.htm
“Aerlinte Éireann Teoranta” EI-ACR, ACS, ADA, ADD
“…Dublin-Rome routes”
The old airport CIAMPINO had railroad tracks east of threshold of runway 15

Yes I do believe that you have it Wieesso. One of the blokes on the Irish forum told me that Aer Lingus operated a short-lived service to Ciampino using the Constellation so this is probably where it is. My father was with this particular flight as there is a picture of him in front of the aircraft. It is nice to get that one nailed down.