Go to the swimming pool of submarine academy (it seems to be in Guangxi Road, Qingdao, just changed. The telephone number there can be called 1 14). The swimming pool of Qingdao Submarine Academy is probably the cleanest swimming pool in Qingdao. Because of soldiers' daily training, water is changed frequently and the price is not very expensive, but the opening hours are limited (because of soldiers' daily training).