Bollo Brook
Bollo Brook or Bollar Brook is an underground river in Middlesex which ultimately flows into the River Thames.
Bollo Brook rises on what is now the site of Ealing Common tube station to the west of Acton and follows a roughly south-easterly direction. Its river bed is obscured today as the Piccadilly and District lines now run over it. Ponds fed by the river shown on earlier maps, such as the fishponds by the London Transport Museum Depot (where Acton Town tube station stands) have now gone.
The Bollo Brook continues to where it enters the grounds of Chiswick House. There it is joined by a stream from a lake near Sydney House to the west. The waters feed the lakes and fountains at Chiswick House, and then drain into the River Thames downstream of Barnes Bridge[1]