I always thought a ‘cistern’ was something positioned over a toilet that either served as a tank for the flush water or somewhere that assassins could pick up a gun in a plastic bag. When we got a new cistern for our upstairs loo I was a bit disappointed to find there was no free gun with it.

Cisterns can also be used for storing rainwater, and they can get quite large. There is a huge underground one in Istanbul called the Basilica Cistern and it must have powered a mega-size of toilet flush. The Ottoman Sultans were very wealthy and they could probably afford the largest toilets in the known world, and probably gold-plated. I’m guessing that feasting on all that Turkish Delight gummed up their bowels, as it did mine. So, when the dam did finally burst (metaphorically speaking), they probably needed something with a bit of welly to clear the pan.

I had to make do with the toilet on Turkish Airlines flight TK0694 to Cairo which really wasn’t up to the job, as I demonstrated to the air hostess. It’s strange what they count as air-rage these days.

The Basilica Cistern is a huge underground water storage facility with a forest of stone columns that hold up the ceiling, which stops the rest of Istanbul from falling in. Two of the columns have ancient sculptures of the head of Medusa the Gorgon at their bases. One Medusa is upside down and the other is sideways. It is said that this unusual orientation was meant to reduce their magical powers. Medusa was the mythical creature that was so ugly you turned to stone if you looked at her. However, as both of these heads are already made of stone, I’m assuming these Medusas came across each other on a night out in Istanbul and had a staring competition.

The Basilica Cistern was used as a location in ‘From Russia With Love’, which was a proper James Bond film with a proper title. More recently Istanbul’s Grand Bazaar was also used as a location in one of the latter-day Bond films. It was called ‘Skyfall’, whatever that means. Bond films these days don’t make a lot of sense and Sean Connery certainly wouldn’t have put up with it. They also lack any realism. When I visited the Grand Bazaar, I ended up being relieved of all my Turkish Lire by various peddlers of tourist tat. In Skyfall I didn’t see Daniel Craig getting conned into buying a porcelain cat wearing a fez.

I also visited the Topkapi Palace on my trip to Istanbul. This is where the wealthy Sultans actually lived. You can buy an additional ticket to gain access to the Harem. This was a bit of a rip-off because there aren’t any scantily-clad ladies there any more, and there haven’t been for many years. Presumably it’s been long enough for them to get around to mentioning it at the ticket office, before you buy a ticket.

The Sultans got very protective of their possessions and they had proper eunuchs to look after the ladies. There is a Courtyard of The Eunuchs as you enter the Harem. This was the first line of defence that would face any intruder sneaking into the harem for a bit of illicit naughtiness. The eunuchs were heavily-armed, devoted to their task and they would fight to the death to protect the ladies of the Harem. They certainly had balls.