What is "foinavon"

Foinavon (1958–1971) was an undistinguished Irish racehorse, until he won the Grand National in 1967 after the rest of the field fell, refused or were hampered or brought down in a mêlée at the 23rd fence. The fence was officially named after Foinavon in 1984.

He was at one point owned by Anne Grosvenor, Duchess of Westminster, whose colours were also carried by Arkle. Both were named after Scottish mountains.