Attendees of the 1969 IEC (<a href="http://www.iec.ch/" rel="nofollow">International Eletrotechnical Commission</a>) subcommittee conference in Moscow ride a sight seeing tour boat between stops on the Moscow River.
Borodinsky Bridge behind them.
Photo by my grandfather David C. Cook. Scanned from an unlabeled Kodachrome slide, date stamped June 1969 and numbered W1 10. In an unlabeled slide cartridge.