On winning the gold medal in the women’s kata event at the Tokyo 2020 Olympics, Sandra Sánchez waved a blue-white-blue horizontal triband flag with a coat of arms in the center. The coat of arms includes a crown on top of what seems to be a fortified tower with a red background.
I am trying to find out what this flag represents. I searched through flags of autonomous communities in Spain and flags of Spanish cities, and also tried to use flagid.org, but couldn’t find it.
The full flag can be seen in this YouTube video from Eurosport (at 5:19). I am also posting a partial screenshot showing the colors and coat of arms here:
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