Nishiyama Onsen Keiunkan local Hakuho Springs. The hotel was last renovated in 1997 and has 37 rooms. Nishiyama Onsen Keiunkan Nishiyama Onsen Keiunkan (西山温泉慶雲館) is a hot spring hotel in Hayakawa, Yamanashi Prefecture, Japan. Founded in 705 AD by Fujiwara Mahito, it is the oldest hotel and one of the oldest companies in operation. In 2011, the hotel was officially recognised by the Guinness World Records as the oldest hotel in the world. It has been continuously operated by 52 generations of the same family (including adopted heirs) for over 1,300 years. The Keiunkan lies at the foot of the Akaishi Mountains. Since
Onsen found in some onsens with poor sanitation. Revelations of poor sanitary practices at some onsens have led to improved regulation by hot-spring communities to maintain their reputation. There have been reports of infectious disease found in hot bodies of water worldwide, such as various "Naegleria" species. While studies have found the presence of "Naegleria" in hot spring waters, the worrisome "Naegleria fowleri" amoeba has not been identified. Nevertheless, fewer than five cases have been seen historically in Japan, although not conclusively linked to onsen exposure. Many onsens display notices reminding anyone with open cuts, sores, or lesions not to bathe.