Interlisp was a "West Coast" historic Lisp dialect and development environment descended from LISP 1.5.

Interlisp ran on the PDP-10, Xerox Lisp machines, VAX, and SPARC. There is both a commercial and a free implementation of Interlisp available for modern machines.

The Computer History Museum hosts many Interlisp manuals:

A good overview of Interlisp is available in the paper The Interlisp Programming Environment by Warren Teitelman and Larry Masinter: