Arnold is a census-designated place (CDP) in Calaveras County, California, United States. The population was 3,288 at the 2020 census, down from 4,218 at the 2000 census. Arnold is located on State Route 4. The Arnold area is a scenic playground with something for everyone!

Natural Bridges Trailhead is located in Vallecito, California. It has a full loop of 9.8 miles (15.8 kilometers) and passes all three natural bridges. The Natural Bridges trail is a beautiful two-mile round trip hike will lead you to spectacular limestone caverns that have been carved out by Coyote Creek which feeds into New Melones Lake.

The California Cavern State Historic Landmark is a fascinating underground attraction located in Mountain Ranch, California. It is situated in the Sierra Nevada foothills, near the town of Mountain Ranch in Calaveras County, California. It is nestled within the picturesque landscape of the region, surrounded by oak woodlands and rolling hills.

Moaning Caverns Adventure Park is a popular attraction located in Vallecito, California, USA. The park is centered around the Moaning Cavern, a large cave system that visitors can explore on guided tours. Moaning Caverns was discovered in modern times by gold miners in 1851, but it has long been known as an interesting geological feature by prehistoric peoples.

Mercer Caverns is a popular tourist attraction located in Murphys, California. It is situated in the scenic town of Murphys, which is located in Calaveras County in the Sierra Nevada foothills of California. The caverns are nestled within the picturesque landscape of the region. Visiting Mercer Caverns is an opportunity to explore the fascinating underground world and witness the natural beauty of the cave formations.