Over the weekend in the far north of the Western Australia Kimberley cattle stations put their mustering horses to the test and battled it out at the Derby race track.

The annual Derby Picnic Races, which is a fundraiser for the local School of the Air, only allows station horses and riders to compete for the cup.

This year history was made when Troy Haslet from Meeda Station won the Margaret River Station Cup in a photo finish over long time reigning station Napier Downs.

Napier Downs had won the cup for the last seven years, six of those on now retired stock horse Emma.

Mr Haslet says he didn't expect to the win the race, let alone rider of the day.

"We just got him out a few weeks ago of the spellers paddock and trotted him a few times and gave him a few gallops up the air strip."

Margaret River Station has sponsored the event for over 20 years and this year despite it being sold to Kimberley pastoralist Haydn Sale the tradition continued.

Mr Sale says he decided to continue to sponsor the event due its importance in fundraising for the school.

"We have kids in school of the air ourselves and it's a fantastic service so it's a good cause.

"Also Mary and Doug Dixon I believe sponsored it for 25 plus years so it would be a pity to stop that history of Margaret River Station being involved."