Zuo he shan you yuan, Hikone

Sawayama Amusement Park is an unfinished amusement park located in Hikone City, Shiga Prefecture. It is operated by the Sawayama Sanseikai Foundation.

Construction began in 1976 by Iwao Izumi, a local builder, with the idea of creating a theme park dedicated to Mitsunari Ishida, who resided at Sawayama Castle. The theme park was to be centered on the restored Sawayama Castle and include a history museum, art museum, and playground facilities, but it was never officially opened.

It faces National Route 8. Most of the buildings and exhibits in the amusement park were privately built by the industrialist who conceived the idea. While the park was open to the public free of charge, expansion and renovation work continued. There are two entrances, both of which have a sign that reads "Feel free to enter, Sawayama Sanseikai," and anyone can enter for free; one of the two entrances has a shed, a fence, and a counting gate, suggesting that an entrance fee was charged in the past. Sawayama Castle itself has no entrance and is inaccessible. Although it is not listed in any official pamphlets or tourist maps, it has recently become known as a B-class tourist spot through the Internet and other media.

In March 2000, it was reported that antiques in the facility were stolen. At that time, the museum was reported as "Hikone's Private History Museum," indicating that it was still open at that time.