Dark Island

Within the walls is a network of secret passageways that are accessible from various locations, one of which is a panel in the library that, at one time, could be opened by pulling a specific book from a nearby shelf, triggering the locking mechanism.

Because of the depth of the channel on one side, and the relative shallowness on the other, it is very good for sport fishing of largemouth bass and northern pike.

They contended that Dr. Harold Martin, director of the charity, maintained the tax-exempt property for his own private use as a summer residence.

Martin prevailed in court, on the basis that he and his wife, Eloise, offered a religious service on the island every Sunday morning, open to all.

Advertisements appeared in high-end real estate magazines such as Unique Homes with suggestions that it be a "private residence, corporate retreat or hunting lodge."

Interest came from as far as Japan, but the property remained unsold until acquired in 2001 by Dark Island Tours, Inc., a venture of German businessman Farhad Vladi and two European business partners.

Unlike nearby Boldt Castle, Dark Island always served as a private residence, until opened to the public for tours.

The Canadian folk rock band Great Lake Swimmers recorded part of their 2009 album Lost Channels at the castle.