Gene O'Neill's photostream  

On the grounds of the Philadelphia Navy Yard

More Middlesex fauna

From Wikipedia

Tripod Rock is glacial erratic located in Kinnelon, New Jersey in Pyramid Mountain Natural Historical Area. This famous multi-ton boulder is balanced on three smaller boulders. It is 15 feet long, 12 feet wide, and 8 feet high. There is a peculiar triangular crest running the length of its top. The entire boulder is balanced two feet above the bedrock on three smaller stones. The point of contact between the main boulder and its support stones formed an approximate 3-4-5 triangle.

About 30 feet away from Tripod Rock stands a boulder arrangement which appears to form a triangle. Two large boulders balanced partially on two smaller stones for the base. The apex is about 15 feet away and in the form of a smaller rock. The apex of the triangular configuration points to a hill forming the horizon. Intriguingly, it has been observed that this sightline forms the setting point of the sun on the summer solstice.

There are also two smaller "Tripod Rocks" about 10 feet away from the large one, the smaller ones are about 4-7 feet wide.