I first went here in May 2010. It’s a fascinating place with huge blocks of stone; stone walls, metal cables strewn around all over; rusting pieces of machinery etc. I wasn’t happy with the pictures I got with my then carry around camera: a Pansonic Lumix ZS3. So I thought I’d go back.

The New York-New Jersey Trail Conference has this to say:

Tucked away on a hillside in northern Westchester County, NY, Sylvan Glen Nature Preserve is the site of a former quarry which supplied a honey-colored granite for the approaches to the George Washington and Whitestone bridges. The property was purchased in 1981 and was opened as a park when additional adjoining properties were acquired. Quarries of various sizes and remnents of the operations are located throughout the western portion of the park. Subsequent acquisition of adjacent land extended the park onto former farmland and provided another entrance to the park.
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Old cables, discarded slabs of granite, and an explosive shed are a few of the remnants along the trails in Sylvan Glen Park Preserve, the site of a former quarry. Other features in the park include: Lime Kiln and shell middens; Quarry Oak (approximately 400-500 year old white oak – 220 inch circumference, 104 feet height, 102 feet spread); Riding ring which is the Ring Trail.

The following article provides a lot more historical information for those who are interested:

Grenci, Ellis and the Mellow Golden Granite of Mohegan Lake, North County News, March 4-10, 1981by Charles Morrill

Pullies and cables

Cables

Rock archway.

Pond – or is it a flooded quarry?

Explosives shed.

View from High Quarry Trail