This castle fell to the forces of Ukita Naoie in 1579 (Tensho 7).

This medieval mountain castle is believed to have been built by the Sasabe clan during the Sengoku period. A replica castle tower (castle-shaped observation deck), constructed in 1988, stands in the main compound and has been designated a city-designated historic site. Remains of the moats, earthworks, moats, vertical moats, and wells remain clearly visible, and from the top of the mountain, visitors can enjoy a breathtaking view of the surrounding towns of So, the Yoshii River, and the distant Chugoku Mountains. With a nearly 360-degree view, it's clear that the castle's location at the time gave it an advantage against attacks from all sides. Its appeal lies in the fact that it serves as both a spectacular castle ruin and a viewpoint all at once.

In spring, the approximately 300 cherry trees in Yoshii Castle Park decorate the mountainside, creating a photogenic scene that complements the wooden exterior of the replica castle tower. Inside the observation facility, there are exhibits of roofing tiles, pottery, and Bizen ware unearthed during the excavation, allowing visitors to imagine what life was like in the past and the castle's structure.

[Useful Concerns]
The southern route to the site is a very narrow mountain path, so it's best to avoid it. The route from the Yoshii B&G Marine Center on the north side has more space.

The parking lot is located just below the castle. However, the road is narrow for about 300 meters from the castle. There is a large parking lot 300 meters ahead.