The Upperville, Virginia estate of late heiress Rachel “Bunny” Mellon recently hit the market for $70 million Called Oak Spring Farm, the 2,000-acre property includes a 10,000-square-foot Georgian mansion, a mile-long airstrip, a working dairy, two stables with 43 stalls, barns, more than 20 cottages, and extensive gardens.Mellon, an heiress to the Listerine mouthwash fortune, died in March at age 103. She was the wife of the late Paul Mellon, son of financier Andrew Mellon, who acquired the estate is the 1930s.