Faith Martin-Porter fired home following an excellent solo run to give Hill House the lead and breach Bromley’s defence for the first time on finals day.
Sasha Kelbrick equalised to set up a tense finish. With the game heading towards a shootout, Bromley won a penalty corner in the dying seconds that was converted by Louise Coley to ensure her school returned to London as champions.
Hill House had topped their pool with two wins and a draw. They were crowned north east champions in November to book their place at the national finals.
James Ross, Hill House’s director of hockey, said: “This group have worked very hard and grown so much this year.
"This is our third visit to the nationals in recent years and to get within five minutes of winning the cup is a wonderful achievement for the girls, the school and for hockey in this part of Yorkshire.
“Our hockey programme is growing and developing each year, with more and more keen hockey players coming to the school to be a part of it. We hope to return next year and go one step further.”
Hill House had earlier made a good start to finals day by beating Bristol’s Queen Elizabeth’s Hospital School 1-0 thanks to a goal from Lulu Morrison-Parry.
A strong Oxford High School proved to be formidable opponents but a late Niamh Doody equaliser earned Hill House a hard-fought draw.
An excellent performance against Woodbridge School, the East of England champions, then resulted in a 2-1 victory courtesy of goals from Morrison-Parry and a late Eve Bishop winner.
Mia Austin impressed throughout the tournament with her defensive organisation, while captain Charlotte Westmoreland-Smith was one of the competition’s stand-out goalkeepers.
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