Gertrude Jekyll: Munstead Wood Inspires Pool

A 40 acre Alabama garden I'm working on has the bones of Gertrude Jekyll's home, Munstead Wood, below.
I've been asked to put in a swimming pool off the back terrace. Seeing these curves, above, I knew immediately how to shape the swimming pool.

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How do I design 40 acres? I start at the house.

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Garden & Be Well, XO Tara

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Pic via internet. All my travels in England, and never to Munstead Wood.