Place of a skull
Mark 15:22 ¶ And they bring him unto the place Golgotha, which is, being interpreted, The place of a skull.
On the north side of the Old City, just on the east side of the street which leads north toward Damascus is the escarpment. It was formed when mount Moriah was dug out (quarried) leaving a long meandering cliff. On the east side of this cliff (which faces the south toward the city wall) is what looks like a skull formed unintentionally when the stones were quarried. This is even visible from high altitudes overlooking the city. There is a viewing station at the Garden Tomb for this 'rocky skull'.
This is where public stonings occurred. The first Christian martyr, Stephen, was stoned here.