The remains of Hadliegh Castle in Essex, England, overlooking the Thames Estuary.
This castle has been a ruin for longer than it was active. Local knowledge says that it was built on unstable ground and half of it collapsed down the cliff one wild and stormy night, many centuries ago. Doesn't look like there's much left of the rest, to be honest, but the view out across the Thames Estuary is wonderful.
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