The coords above are NOT for the
cache, but for a convenient tube and rail station both
for caching and as starting point to explore the area. I recommend
going there by public transport or bicycle, some parking may be
available but as usual in London it tends to be limited and/or
expensive.
I'm sure everybody has heard this "music" sometime, and has no
problem to "play" it. Now your task is of course to listen to
it!
Listen here
NOTE: The file linked above is a standard WAVE Windows
audio file, which most computers should have no trouble to play,
either within the browser or in your default audio program. The
file is hosted on an external server and therefore outside of
control and responsibility of Groundspeak. It can do no harm to
your computer, but in case somebody is afraid of downloading
external data, and in order to comply with geocaching.com
guidelines, there's an other option to solve the puzzle below.
It would be interesting to see in your log if you used the audio
file or image to get the coords. Note that Terrain rating may be
inverse proportional to cacher's length 
Alternative puzzle - find the coords in the image below.
If you're not sure about your solution, you can check it here. You're looking for a 35mm-micro.
Stealth required, also mind the window muggles.
Please take care to replace the cache exactly
as found.
Wheelchair Users
Location is wheelchair friendly, however the cache retrieval is
probably impossible from a wheelchair, so a helper may be
needed.
