between the 1760s and 1840s, not to be seen by most of the people who've lived here since.
I'm indebted to Thames Water for this venture into the depths of our city, and am very privileged in being able to become one of the few Londoners to actually see this part of our fantastic capital. It will certainly give a new angle to two stories I regularly cover on here - flooding when it rains in Hammersmith and parts of Shepherd's Bush and also the long running saga over the Thames Tideway Tunnel. At their heart both of those stories relate to the need to upgrade Joseph Bazalgette's Victorian sewer network which was built for a London much smaller and not subject to the predicted growth in storms as our climate changes.
My own fascination with London partly led to the setting up of this blog - the stories you can find in our corner of the big city are fascinating windows onto our disappearing past - just look at this shop which is still there on the Uxbridge Road but which had a coach & horses crash through it in 1912! It's also why I went on this tour to explore an old disused tube station in Aldwych, and it's most certainly why I am very pleased the traders of Shepherd's Bush Market appear to have won their battle to save the historic row of shops on Goldhawk Road from rapacious property developers Orion.
So think of me on Thursday, walking along an ancient river which is rarely seen but always there, admiring the brickwork of Victorian builders and all ... in the centre of town!
I'm told it might smell a bit too. And just look at the waders I have to wear. Tsk.
0930 UPDATE: I've been taken to task by one of the several readers who are also BBC journalists for using the phrase "Fleet River" instead of "River Fleet". The former is an Americanism I'm told and I should know better. On balance, they're probably right so I stand humbled and corrected.
0950 UPDATE: But not as humbled as James Naughtie this morning, who had his own brand of the Queen's English it would seem.