Hikone Castle is a Japanese castle located in Hikone city, Shiga Prefecture, Japan. It was built in 1622 by Ii Naokatsu, a Japanese feudal lord, as a residence and fortress. Hikone Castle is considered one of the finest surviving examples of early modern Japanese castle architecture and is listed as a National Treasure of Japan.

The castle is built on a hilltop overlooking Lake Biwa, which is the largest freshwater lake in Japan. Its design includes multiple layers of defense, with walls, moats, and gates. The central keep of the castle is a three-story structure made of wood and plaster, and is the only original castle keep in Japan that still retains its original appearance.

Inside the castle, there are various exhibits showcasing the castle's history and artifacts from the Edo period. Visitors can also see the original shachi, a mythical creature used as a roof ornament on Japanese castles, which is displayed on the roof of the castle keep.

In addition to the castle, the Hikone Castle complex includes various gardens, gates, and other buildings that provide insight into Japanese castle architecture and life during the Edo period. Hikone Castle is also known for its cherry blossom trees, which bloom in the spring and attract visitors from all over Japan.

Hikone Castle is a popular tourist attraction and is easily accessible by train from Kyoto and other major cities in Japan. It is a symbol of Japanese feudal architecture and culture, and is a must-visit destination for history and architecture enthusiasts.