Photo by NCinDC.Built in 1912 by architect Charles Adam Platt for owner James Parmalee, the Causeway (as it was known then) is a 20 acre estate with open fields, woodlands, stone bridges, formal gardens, a pond, and meandering streams in the Cleveland Park neighborhood. Now a part of the Washington International School, the estate hearkens back to when the neighborhood was comprised of farms, summer houses, and isolated suburban estates like the Causeway. The…