Tower Bridge, one of the finest, most recognisable bridges in the
world, has stood over the River Thames in London since 1894.
This photo shows some of the active boating traffic during a low
tide in 2003. The river Thames is tidal, the river changes in height
by around 6 metres [20 feet] between the low and high tide.
In 1977, Tower Bridge was painted red, white and blue
to celebrate the Queen's Silver Jubilee.
(Before that, it was painted chocolate brown).