As a follow-up to the February 4, 2022 post on "The Great Wall of East Hills", Roslyn Landmark Society member Greg Oreiro wrote this article documenting the remaining remnants of the wall.

Clarence Hungerford Mackay's Harbor Hill Estate once stood at the highest point in Nassau County in Roslyn (now East Hills.)

Clarence Mackay (1874-1938) was the heir to the Comstock silver fortune and was a major figure in the development of the international telegraph business.

The 1-mile long south drive extended from the Mackay Estate Gate Lodge at Harbor Hill Road and Roslyn Road (currently being restored) and wound its way up the second largest hill on Long Island to the front of the mansion.

Graphically overlaid on top of a current satellite view (courtesy of Frank Femenias) one can see that the main drive followed the current Mimosa Drive for about 1,500 feet before turning 180 degrees to wind up the hillside.

The re-discovered section can be seen on historic Google Earth imagery from 2016 and includes inner and outer retaining walls never before recognized.

The drive, seen here shortly after completion, is believed to be in the location of the current Mimosa Drive. The ivy-covered outer retaining wall on the right.

The 16-foot-wide drive with stone gutters and beautiful landscaping built along with the mansion between 1900-1902 cost roughly $150,000 alone (about $5 million today).

Some famous visitors to Harbor Hill included Charles Lindbergh after his Trans-Atlantic triumph in 1927. This view of the west gardens was taken during a party after Lindbergh's New York City ticker-tape parade. The Prince of Wales and even Cardinal Eugenio Pacelli, the future Pope Pius XII, have been on this historic drive for celebrations at Harbor Hill.

As stated by Al Velocci's comment in a previous post , to construct the country home and the drive, about 166,000 tons of granite*, at a cost of $117,006*, was purchased from the 4-acre demolition site of the 1840's reservoir at 5th Ave & 42nd St in 1898. The reservoir can be seen in this photo from the 1870's.

*Source: Richard Guy Wilson's book, 'Harbor Hill Portrait of a House'.

On the site of the former Murray Hill/Croton Reservoir now sits the New York City Public Library. In the lower section of the library, the original foundation of the former reservoir can still be seen.

A recent re-discovery by the Roslyn Landmark Society uncovered a long, 300-foot-long section of his 1-mile front drive to the front of Harbor Hill buried behind the homes on Mimosa and Ash Drives. Exciting, as this particular section has gone unnoticed except by residents for decades. In this image, the drive was on top of the wall.

With the explicit permission of the kind and curious residents along Mimosa and Ash Drives, members of the Roslyn Landmark Society were allowed on their private property to document this long-forgotten stretch of driveway. In this image, the drive was in front of the wall, excavated to make room for the house,

Longer view. The drive again was in front of the wall, partially excavated in the early 1960s for the backyard.

The most surprising discovery was the unknown presence of not one, but two walls consisting of an outer and inner retaining wall for the drive seen here. Both walls clearly seen here as the drive continues up the hillside. Residents were thrilled to finally know the history of the double walls that loomed in their backyard for decades. The property that the entire wall sits is all private and please do not trespass to view it. A utility pole marks the middle of the drive surrounded by walls on both sides.

The top of the hill where it turned inward and over Ash Drive. Heavier stone can be seen at the bottom for support and base of the drive, and lighter stone used on the upper portion creating the guardrail of sorts seen in the previous photo after completion. In this image, the drive was behind the wall.

Standing on the actual drive towards the top looking at the outer retaining wall. The drive in this view was to the right of the wall.

A different section of the wall behind a house or as the resident (recently from Israel) likes to call it, her 'Wailing Wall'. The drive was on top of this section of the wall. This particular small section was previously documented and photographed by Roslyn historian Roy Moger in 1963.

This same granite was used all over the estate. Here, the still existing Harbor Hill Water Tower is built in the same fashion and stone as the drive.

Thanks to all the East Hills' residents who allowed the Roslyn Landmark Society to document this forgotten piece of history. The wall sits on private property. Please do not trespass.