My friend Kenkichi Yagi, who lives in Otsu, wrote an interesting story about his sailing trip around Lake Biwa in 1966. He went with another friend and was able to complete the haphazard, adventurous trip in 2.5 days on a small yacht.

His story is in English now with pictures:

http://yagiken.cocolog-nifty.com/yagiken_web_site_english/2006/12/biwako_circumna.html