Britain's Adam Peaty completed the 'quadruple-quadruple' by claiming his fourth title of the week at his fourth consecutive European Championships.
The Olympic champion, who had already won the 50m and 100m breaststroke events as well as the mixed 4x100m medley relay, completed the set with the men's 4x100m medley relay team.
"I'm so excited about what the team and I can do at the Olympics," he said.
The women's 4x100m medley relay team also claimed a dominant gold.
Cassie Wild, 20, produced a stunning swim to secure a shock 200m backstroke silver.
Ben Proud took 50m freestyle silver, with James Guy and Max Litchfield battling to respective 100m butterfly and individual medley bronze medals.
The World Championship gold medal-winning quartet of Luke Greenbank, Peaty, James Guy and Duncan Scott finished the 4x100m medley relay final in a new championship record of three minutes 28.59 seconds.
It is the fourth time Peaty has won all four events he has entered at a European Championships following previous successes at Berlin 2014, London 2016 and Glasgow 2018.
The women's team were led off by a new British and European record of 58.08 seconds by 100m backstroke gold medallist Kathleen Dawson before Molly Renshaw, Laura Stephens and Anna Hopkin combined to bring home the team in 3:56.91.
"It's great to finally get that time here and it's been such an amazing event for the British team which I think helped me as well," Dawson told BBC Sport.
Wild entered her maiden major international competition for Great Britain with a personal best of 2:10.94 in the 200m backstroke, but dropped more than three seconds from that time throughout the event and set a new mark of 2:07.74 in the final.
"To be honest I've always considered myself a 100m swimmer and I don't really like the 200m, but I guess I'm going to have to swim a few more of them," she said.
The British team finished top of the medal table with a stunning total of 26 medals (11 golds, nine silvers and six bronze) from seven days of racing.
Freya Anderson, James Guy and Tom Dean finished with six medals each.
"We have done so much swimming this week and we're all absolutely shattered, but we race for one another and we're looking in a great place ahead of the Tokyo Olympics," Guy said.