The blaze "engulfed" the roof which then collapsed into the flat, destroying everything inside.
The 17-year-old victim was taken to hospital with life-threatening injuries, police say.
All the details from the final day of the 2018 meeting where Ryan Moore finished top jockey.
Patrols have been operating at railway stations in the Thames Valley for the past three years.
The medieval abbey was closed 10 years ago when large stones began to fall from the walls.
Great Britain's Joe Clarke and Mallory Franklin claim bronze medals in the first event of the 2018 Slalom World Cup in Slovakia.
Jockey Ryan Moore seals a big-race double at Royal Ascot with Merchant Navy while favourite Harry Angel is injured at the start of the Diamond Jubilee Stakes.
Windsor and Maidenhead Observer
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