10. Garvan Estate
Very little remains of the Francis P. Garvan estate, a Tudor-style home, built in 1891 and located in the village of Old Westbury (on the southern fringe of the Gold Coast). Once known for its stretch of stables and gardens, all that remains of the estate (also known as the Roslyn House) is an original brick garden wall. In 1974, a developer purchased the property with the agenda to subdivide the estate and tear down the main house.
Today, the brick wall surrounds a newly constructed home instead of the previous vintage mansion known for its impressive landscaping. According to The New York Times, the tax burden is one of the main reasons owners ultimately decide to demolish such mansions.