mosh pit. slam dancing

[Sam Clements]

In a thread over at Straight Dope, we're trying to find out the first "mosh
pit."  Did it occur in NY or LA?

The respondents seem to have a grasp that it evolved from "slam dancing."
They also seem to know that, in the beginning, there was only mosh.  The pit
came later.  RHDAS says "see 'pit' for 'mosh pit' " so, of course,  we'll
all get to view that later.

The RHDAS cites mosh as a verb from 1983, Village Voice.