Preston Castle is located about a half mile north of the City of Ione. It was established as the first building to house juvenile offenders within the complex now known as the Preston School of Industry. The establishment of the school was provided for by an act of the State Legislature in 1889 and was named in honor of the late Senator E. M. Preston of Nevada County, California.

The fact that the building was planned and built as a school and not a prison is standing evidence of correctional reform trends, for juveniles in the State of California which took a giant step forward with the opening of the Preston School. It represents the State's first major attempt at prison reform for young offenders.

Preston Castle is the most significant representative of Romanesque Revival architecture in the Mother Lode region. The eclectic architectural style evident in the castle design is very similar to the inner city schools of the period throughout the nation.

The bricks for the castle were secured from a brick yard in lone and the sandstone came from a nearby quarry. It is difficult to estimate the exact number of rooms in the beginning, since in past years many partitions have been put in or taken out, but it is estimated there must have been about 120 rooms.

Adapted from the NRHP nomination.

Preston Castle is owned by the State of California and leased to Preston Castle Foundation which is working to transfer ownership to the city of Ione. The foundation offers tours, including Overnight Ghost Tours. According to the foundation website:

You will have access to three floors of the Castle throughout the night with only your flashlight and paranormal investigation gear along for comfort.

If you are reluctant to trespass at Briarcliff Asylum on a dark and stormy night, a night in Preston Castle might be equally salubrious.

Preston Castle is also California Landmark 867.