Ros Canter won individual eventing gold as Great Britain took the team title at the World Equestrian Games in the USA.
Piggy French, Gemma Tattersall, Tom McEwan and Canter ensured a sixth world title for Britain, adding to the most recent success in 2010.
Canter's final run on Allstar B in the jumping test propelled her into first position in the individual competition.
"It's just the most incredible feeling," Canter said, "I can't believe it. There were quite a few tears when I found out, which isn't normal for me. Allstar B was absolutely amazing - he was an absolute hero."
Canter is Britain's first individual equestrian world gold medalist since Zara Phillips, who was voted BBC Sports Personality of the Year after her 2006 triumph.
Germany's Ingrid Klimke failed on the final fence to finish third and Ireland's Padraig McCarthy won individual silver.
The day's competition was scheduled to take place on Sunday, but was postponed because of Storm Florence.
Britain moved into the gold-medal position following Saturday's cross-country phase, but mistakes from Tattersall, McEwan and French meant their lead had been cut to a fraction by the time penultimate rider Canter came in.
She delivered a flawless round to confirm team victory, while also moving into first place in the individual standings.
What a week! Well done Team GB!