And finally in this series, the West End's lost river. That'll be the Tyburn, a long-departed stream which used to run through some of the most tourist-friendly spots on the planet. The Queen lives on it, Big Ben overshadows it, and shoppers on Oxford Street regularly wade across it. Even better, its valley remains readily visible most of the way down, even through Marylebone and Mayfair, should you ever fancy tracking it down. I've had a go.
The River Tyburn started its journey from the uplands of Hampstead, as did its streamy neighbours the Fleet and the Westbourne. All three ran sort-of parallel down to the Thames, with the Tyburn sandwiched inbetween the other two. It trickled south through St John's Wood, keeping to the west of the heights of Primrose Hill, and then into what is now Regent's Park. The boating lake here is the river's most obvious legacy, but one of the bridges over the Regent's Canal hides a similar secret. The Tyburn slipped out of the park past Baker Street station and on into Marylebone, where meandering Marylebone Lane still mimics the river's former course. Oxford Street is crossed close to Bond Street station (look for the very obvious dip in the road when you're out Christmas shopping). Then on into the heart of Mayfair (via Brook Street, obviously), curving around Berkeley Square to cross Piccadilly and into Green Park. The original stream crossed the front of Buckingham Palace before swinging east through St James's Park (home to another no-coincidence water feature) and splitting in two. These final rivulets once surrounded Thorney Island, a dry-spot in the marsh upon which Westminster Abbey and the Palace of Westminster were built. Drainage hereabouts later forced the diversion of the river south, with a fresh course running down to Pimlico. One river, three possible endings, all now long gone.
There are several theories as to the derivation of the name Tyburn. The 'burn' bit is fairly straightforward, being derived from 'bourne' which means stream. But the first part of the name is probably linked to that split in the lower river. It could therefore come from 'Teo' (meaning 'two') or 'Tie' (meaning 'enclosing'). The first of these is given credence by King Edgar's royal charter, dated 951AD, which names the stream Teo-burna. Alternatively the entire name may mean 'boundary stream', or else might be a contraction of 'the Aye bourne', whoever or whatever 'Aye' was. Take your pick.
Other places named after the Tyburn: Oxford Street: Until the 1780s, known as Tyburn Road Tyburn: A small medieval village at the western end of Tyburn Road (population in 1086, eight families) Tyburn Tree: Site of London's most notorious place of execution, in Tyburn, close to where Marble Arch now stands. Tyburn Brook: A completely different lost river, a tributary of the Westbourne, which flowed from the gallows southwest into Hyde Park Marylebone: Parish whose was church originally known as 'St Mary's church by the bourne'.
The river Tyburn's fate was decreed by its location. Early settlers were drawn to its delta, at Westminster, to form London's second nucleus. Its lower marshes were drained in Tudor times to create fertile land for farming and hunting. Then, as the city started to extend into Mayfair and Marylebone, the river had to be driven underground to provide sanitary living conditions for new residential quarters. Full burial came in the mid 19th century with the construction of an underground conduit, the King's Scholars' Pond Sewer (named after a pool used by Westminster School's top pupils for fishing and bathing). It's straighter and wider than the old river - for much of its length an elliptical brick tunnel - and still in use for foul-smelling run-off to this day.
Businessman James Bowdidge recently proposed that the Tyburn be restored to the surface, forcibly if necessary, by knocking down all the buildings in its path north of Piccadilly. An most peculiar motive for a property developer, it has to be said, but James is also the honorary secretary of the Tyburn Angling Society so claimed his priories were mostly fish-related. Assuming his plans to be tongue-in-cheek, or at best impractical, your best chance of spotting the Tyburn continues to be searching for clues on the surface.