Somerley Park horse trials is the latest loss to the British Eventing (BE) calender.
The Hampshire event has been running for 18 years.
Organiser Suzie Cotterill, who has been involved with the event since it began, cited costs as the reason for closure.
“It has been an extremely difficult decision to come to since we have been running a very popular event in a stunning location for many years,” she said.
“However due to rising costs associated with the event and location, we simply have to draw the event to a close.”
The event was founded in 1997 by Adele Schardt, who was a long-standing organiser of the affiliated fixture.
She died in 2013 at the age of 59, following a long illness.
“This year was a great success and a legacy to Adele, we will find [another] event that meant much to Adele and have our CIC2* trophy presented in her and Somerley’s name,” added Suzie.
Somerley Park, near Ringwood, hosts classes from BE100 up to advanced-intermediate and also runs a CIC2*.
It holds two events a year in April and June. This year the June fixture was cancelled.
Suzie, who is also on the BE board of directors, thanked the sponsors and organising team.
“I would like to thank everyone for all their kindness and enthusiasm over the years,” she said.
“From the riders, owners and their supporters, to our many volunteers who have endured every weather, as well as the trade-stand holders and our local supporters.”
BE’s chief executive David Holmes also thanked the organisers and host, Lord Somerton, for “many years of dedication” to the sport.
“We are very sorry to see this much-loved fixture lost from the calendar, but will be trying our utmost to find another suitable replacement venue for this region in the near future,” he said.