The Elfsborg swimmer lowered her Swedish record by just over 3.5 seconds on Monday, and in the final she improved it by another 1.6 seconds to 8:31.52.
She has broken her personal record in the event four times since May.
It's been several years of training, but above all the move to the USA. I've changed my training and the big difference is that it's fun to swim. I have a huge team that I train with and for the first time I have a girl that I swim against in every training. I've never had that in Sweden, Häll explains at the record party.
She moved last winter to the University of Louisville in Kentucky, USA, and her development has exploded.
Despite being far behind the field in her first international championship final, she never gave up.
"I felt very relaxed and tried to have fun. Then you always start to question yourself when you meet people who have won Olympic medals, but a teammate in the USA has said that the people you compete against are just an aid to make me swim fast," she says.
Simona Quadarella of Italy won her fourth European Championship gold medal in the 800-meter freestyle with a time of 8:15.55. The Italian has also won World Championship gold and Olympic bronze in the event.
Thilda Häll has the 400 and 1,500 meters freestyle left on her programme. She is also entered for the 200 meters freestyle on Wednesday, but is considering dropping that event.
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