... Department of Physics & Astronomy, Rutgers University, PO Box 849, Piscataway, NJ 08855-0849, U.S.A. Rich cluster CL 0016+16 lies in a large-scale dynamical structure at redshift , and has a strong Sunyaev-Zel'dovich effect. When the X-ray and radio data for CL 0016+16 are interpreted in terms of the cluster distance, this cluster provides the highest redshift datum on the Hubble diagram based on the Sunyaev-Zel'dovich effect, with a Hubble constant of . ... 4 The Hubble diagram . ...