Atagodani Park is a community park in Joetsu with ties to the former Kasugayama Castle and the area’s Sengoku-period (1467–1568) history. The site of the park was once a battle encampment situated on the lower slopes of Kasugayama Castle, the stronghold of the renowned warlord Uesugi Kenshin (1530–1578).

The river flowing through the park defined a natural boundary between the inner and outer castle areas. The river originally ran along a different course, and excavations have shown that embankments were built to redirect its flow. After the castle was abandoned in the early 1600s, a part of the river was dammed and the resulting pond was used to farm lotus root. The lotus pond at the center of Atagodani Park is a remnant of that period.

Today, the park includes a gazebo and a boardwalk surrounding the lotus pond and is a popular place of relaxation and nature study for local residents. The Kasugayama Castle Site is accessible via a flight of stairs near the gazebo.