Jinmu-yama Park, Urban park in Toyooka, Japan

Jinmu-yama Park is a 2.7-hectare urban park in Toyooka, Hyogo Prefecture, centred on a 49-metre hill. It contains the ruins of Toyooka Castle, walking trails, a viewing platform, playground equipment, sandboxes and two public toilets. From the castle's honmaru at the summit, visitors can look over the city centre.

Toyooka Castle was built on this hill in 1580 by Miyabe Keijun. In 1873 a remote worship site for Emperor Jinmu was placed here, giving the hill its name. The city's waterworks, funded by local businessman Nakae Tanetsuzō, were completed in 1922 with a pumping station and distribution reservoir on the hill; a second reservoir followed in 1930. The site became a planned neighbourhood park in 1970.

The park holds about 300 Somei Yoshino cherry trees; in blossom season paper lanterns are lit among them and crowds come for hanami. The name Jinmu-yama dates from 1873, when a remote worship point for Emperor Jinmu was set up on the hill. A bronze statue of Nakae Tanzo, the Toyooka-born businessman who funded the city waterworks, was erected in 1925 in Ju Park.

The summit is reached on foot from Toyooka Station in about 15 minutes on the JR San'in Main Line or Kyoto Tango Railway. Two public toilets serve the grounds, and the paths to the honmaru viewpoint climb steadily, so walking shoes help. The park lies at 12 Kyomachi in central Toyooka, near Toyooka Elementary School, Toyooka High School and the city library.

The grounds contain a working water storage system from the 1920s, among Japan's earliest infrastructure of this kind. Many visitors walk past this part of the park without realizing it serves the city's water supply every single day.