A spokesperson for The Mayhew Animal Home said: "We desperately want to reunite this adorable kitten with their family, as we can’t tell how long they have been missing from home and are sure the owners will be very concerned about the kitten’s whereabouts.
"We’re not too sure how far this little adventurer has travelled, but the pipe is three miles long, starting in Hackney and ending in St John’s Wood in north London.
We really want to make sure that this kitten goes back to its loving family, so please help us to find their owners, and please get in contact with us if you might know who owns this lovely little kitten."
The pipe’s access points are in Millfields Road, Hackney; Eade Road, Haringey; Seven Sisters Road, Islington; Lough Road, Islington; and Pratt Street, Camden.
The Mayhew Animal Home can be contacted on 0208 962 8009.