Scott Durant helped the men’s eight storm to gold while Polly Swann was part of the women’s eight that picked up silver.
The dominant victory for the men ensured Team GB enjoyed a golden finale to the Rio 2016 rowing regatta.
Former Lancaster Royal Grammar School pupil Durant, Tom Ransley, Andrew T Hodge, Matt Gotrel, Pete Reed, Paul Bennett, Matt Langridge, William Satch and cox Phelan Hill produced an exceptional race, following up the women's silver by topping the podium in the final race at the Lagoa.
It was Britain's first gold in the event since Sydney 2000 and was thoroughly deserved after a storming start to the race.
Germany were unable to claw back the leaders, finishing 1.33 seconds behind to the delight of the strong British contingent in the crowd.
The women had kicked things off with their first ever medal in the event, a late surge seeing them take second spot.
Lancaster-born Swann, Katie Greves, Melanie Wilson, Frances Houghton, Jessica Eddie, Olivia Carnegie-Brown, Karen Bennett, Zoe Lee and cox Zoe de Toledo crossed the line in six minutes 3.98 seconds - just 0.12 seconds ahead of bronze medallists Romania.
Reigning champions the United States were deserved winners of a race that Britain started slowly, sitting at the back of the pack at the halfway mark.
However, they upped the ante and entered the final 500 metres in third, before kicking on and holding off Romania to win silver.