This museum is set in the notorious Japanese Germ Warfare Experimental Base (Division 731). Between 1939 and 1945, prisoners of war and civilians were frozen alive, subjected to vivisection or infected with bubonic plague, syphilis and other virulent diseases. Three to four thousand people died here in the most gruesome fashion. The museum includes photos, sculptures and exhibits of the equipment used by the Japanese. There are extensive English captions and an audio guide is available for ¥15.
The base is in the south of Harbin and takes over an hour to reach by bus. From the small bus station at the north end of Tongjiang Jie (通江街), catch bus 348 (¥2). Get off at the temporary stop called Yiliu'er Zhong (一六二中). From there it's a 700m walk northeast to the base. If you get lost, just ask the locals the way to qīsānyī (731). Note that Chinese people can be, understandably, uncomfortable talking about this museum.