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Inwood Hill Park

Inwood Hill Park - Fordham Gneiss in New York City

This text is part of Parks’ Historical Signs Project and can be found posted within the park.

Fordham gneiss, one of the oldest rock formations in the world, can be seen from Inwood Hill Park by looking across Spuyten Duyvil Creek. Named for the Bronx neighborhood where it is most visible, Fordham gneiss was formed around 1.1 billion years ago, in the pre-Cambrian era, during a period of continental shifting. At that time, the continent of North America lay in a narrow basin beneath an ancient, shallow sea. Sand and silt had accumulated in the basin, forming sedimentary rock. During a continental shift, an unidentified landmass collided with North America, thrusting the sedimentary rock upward and forming a mountain range. This collision is known as the Grenville Orogeny, and it occurred at a time when life on earth consisted of algae and bacteria, and multi-celled organisms were beginning to evolve.

The impact of the collision and the high pressures involved caused the sedimentary rock to recrystallize, forming the black-and-white banded, metamorphic rock we see today. The contorted banding pattern of these bands is a testament to the immense geologic force of the shifting plates that formed the gneiss. Over the next hundred million years, passing glaciers and erosion by wind and water wore away the mountain ranges. Further shifting of the landmasses produced Manhattan schist, which can be observed at Inwood Hill Park’s Indian Houses; Inwood marble, named for this area where it can frequently be observed at the surface; and other bedrocks, which all came to rest on or beside the existing layer of gneiss.

In the Bronx, gneiss can be observed running along the surface of the earth in two ridges; one along the west side in Riverdale, and the other along the east side in Fordham, Tremont, University Heights and north into Van Cortlandt Park. Gneiss is also found on Roosevelt Island, emerging from the East River, and in Long Island City, Queens. The rocky cliff that has been painted with the letter “C” and is visible from Inwood Hill Park is one of the few areas in the city where this old bedrock is exposed at the surface.

Directions to Inwood Hill Park

Know Before You Go

There are currently 2 service interruptions affecting access within this park.

Nature CentersInwood Hill Nature Center

Due to the effects of Hurricane Sandy, this facility is closed until further notice.

Baseball FieldsInwood Hill Park

Reconstruction work at the Little League Baseball field will correct existing uneven ball field elevations and will provide a sod infield and outfield. A Scorekeeper’s Box will be installed, player dugout areas will be enlarged and will received new concrete floors, and a clay ‘warning track’ will be installed along the perimeter of the outfield fence to assist playing conditions and maintenance mowing in this area. New bases, clay storage boxes, skinned playing areas and painting and reconstruction of perimeter fencing and backstop areas will also be provided. A metal container will provide secure storage for playing and maintenance equipment with an enclosed player’s warm-up area nearby. New ADA accessible bleachers and an elevated turf viewing area are also being installed to provide seating and viewing areas for the playing field.
Anticipated Completion: Summer 2014

Inwood Hill Park Weather

  • Sun
    Sunny
    61°F
  • Mon
    Mostly Sunny
    67°F
  • Tue
    Chance Showers
    67°F
  • Wed
    Partly Sunny
    59°F

7-day forecast

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