1 Monty: To Çanakkale in Turkey, then!
2 Prof. Jones: We can get a felucca down the Nile and then a ship from Alexandria.
3 Monty: The return train to Cairo might be slightly faster.
3 Minnesota Jones: We just missed it.
3 Monty: Tomorrow then.
4 Minnesota Jones: This is Egypt. The train to Al Balyana runs on Mondays, the return train runs on Tuesdays.

This is based on a true story. Or at least the punchline is.

Or at least... it's based on a story that was told to me many years ago, which I always assumed to be true, but now that I stop and think about it, it may have been a joke way back then too.

I was a student at the University of Sydney, studying for my honours degree in physics. The School of Physics at the university runs its very own radio telescope, the Molonglo Observatory Synthesis Telescope, and I got to use it for my honours year research project. The telescope is sited in a field surrounded by sheep farms, about 25 km east of Canberra. The closest settlement is Hoskinstown (pop. 189), on the road running north to the larger town of Bungendore (pop. 4178) and south to the town of Captains Flat (pop. 610).

Connecting these three places is the Captains Flat railway line. One of the staff at the Molonglo Telescope told us students about the old days of the railway line, when the "Bungendore to Captains Flat Express" used to depart Bungendore precisely at 9 o'clock. On Mondays. And returned at 9 o'clock on Tuesdays.

The Wikipedia page for the train line (which I was not expecting to find!) doesn't have any information about such a once-weekly "express" service. So now I'm beginning to think that the guy who told us naive students this story was being somewhat "interpretive" with the truth for humour value...

Hmmm. It's an odd feeling when you think about something that you were told a long, long time ago, and always assumed was true, but you now suddenly realise was probably just a joke.

UPDATE: Reader Steen from Denmark has achieved a better result on his Research roll than I did, and found an article from the Canberra Times of 26 June, 1994 (archived by the National Library of Australia), which says (in part):

The nearest railway relic to Canberra is the Captains Flat line, a line built long after the boom had subsided and for a specific commercial purpose. In 1937, Lake George Mines Pty Ltd had resumed mining operations at Captains Flat, and payable quantities of copper, lead and zinc were being extracted.

The following year the NSW Government agreed to build a branch line to Captains Flat - a 37km spur from Bungendore on the main Goulburn-Queanbeyan-Cooma line built largely with heavy-duty (40kg a metre) rails. Goods operations began in November, 1939, even though the line was not formally opened until June, 1940. A small passenger platform, the ruins of which remain, was built at Hoskinstown and a stopping place was provided at Foxlow, the only breaks between Bungendore and Captains Flat where the station buildings, complete with platform and signposts, are now a private residence.

The wartime demand for metals provided a boom for Captains Flat, and in its first year of operation some 70,000 tonnes of concentrates were sent out on big 640-tonne goods trains. A thrice-weekly passenger service by rail motor was also provided. By 1951 mine production was in full swing, necessitating two goods trains each weekday running return between Goulburn and Captains Flat.

But the good times ended rather abruptly and 1960 [sic] the rail motor passenger service was withdrawn in favour of a locomotive-hauled passenger train on Mondays, and a goods train with carriage on Wednesdays and Fridays. In 1962, the mine closed down but trains continued to operate to Captains Flat carrying small loads of superphosphate inwards and wool outwards with a further reduction in services. In 1965, local residents successfully resisted an attempt to close the line, but in August, 1968, the end finally came.

The Captains Flat branch line, however, was to have one more flicker of life and glamour: in August, 1969, it was used for the filming of train sequences for the film Ned Kelly, starring Mick Jagger, during which the junction points south of Bungendore were temporarily reconnected to allow a vintage steam locomotive and a couple of antique carriages to be "robbed" by the Kelly Gang. To this day the tracks remain as silent reminders of Captains Flat's brief era of glory.

So this indicates that indeed from 1960 to 1962 there was exactly one passenger service a week, running on Mondays, although it doesn't mention the date of running of the return service. So it seems that my informant wasn't entirely pulling my leg! Which makes me feel a lot better about the whole story.