紧跟伟大领袖毛主席在大风大浪中奋勇前进 -- 庆祝毛主席7。16畅游长江三周年上海市畅游长江活动
Shanghai 1969 Swim the Yangzi River headquarters (上海市一九六九畅游长江指挥部)
The full title:
Closely follow the great leader Chairman Mao and forge ahead courageously amid great storms and waves -- Celebrate the Shanghai movement to swim the Yangzi river to commemorate the third anniversary of Chairman Mao's good swim in the Yangzi river on 16 July.
The orinal photograph was taken by Qian Sijie (錢嗣傑).