Held from October 11 to October 13, the trials welcomed roughly 160 competitors from across NSW and Victoria.

Olivia, who is 13 years old, rode Karrugang Joker and came first in the Junior EVA 60cm division, while Grace, who is 17, rode Arthella Steve and finished a close sixth in the Open EVA 95cm division.

Both girls are members of the Yass Pony Club, and Olivia expressed her pleasure with the weekend.

"[It was] one of the best events so far! [I'm] super, super proud of Zipper [Karrugang Joker] and how he pulled through," Olivia said in an email to the Tribune.

"It was our first ever competition together and he hadn't competed in over eight months after recovering from an injury.

"He is a beautiful and willing horse. All weekend he listened to me and did his very best to do everything I asked of him."

The competition was divided into three phases: dressage, show jumping, and cross country.

After the riders competed in all three, those with the lowest penalty points was declared the winner.

Karrugang Joker's strongest discipline, Olivia said, was dressage, which was the first phase.

"He was listening really well and we pulled off a fantastic dressage test," she said.

"We got a really great score of 66.88 per cent, which put us in second place."

The next phase was showjumping, which took place in the indoor arena and which Olivia described as "a bit scary".

"We got a double clear round, Zipper was strong and energetic going round the course. We ended up in first place after this next phase."

The final phase was the cross country, which got off to an "interesting" start, Olivia said.

"Zipper didn't want to leave all the horses at the starting box and was being a bit spooky approaching the first few jumps, but he got himself together getting a clear round with just a few time penalties," she said.

"Overall ended up in first place. I couldn't be any prouder of Zipper."