The Rispin Mansion is an large, abandoned house, reputed to be haunted, on the intersection of Wharf Road and Clares Street in the town of Capitola, California, USA.
It was built in 1921 by Henry Allen Rispin, an oil executive from San Francisco who had purchased large amounts of the town of Capitola two years before; Rispin was bankrupt by 1929, however, and the house was auctioned off to one Robert Hays Smith. The Smith family never lived in the house, and Robert Smith was himself forced to give up the deed due to financial problems around 1939. It was sold to the Oblates of St. Joseph, an order of Catholic nuns who converted it into a convent; the nuns moved out in 1947, citing problems with cold and with curious trespassers. Since that time, the house has been largely unoccupied; it has, however, been the site of at least one hippie commune and several groups of squatters. It is now owned by the City of Capitola, and plans are under way to convert it and its two acres of gardens into a bed and breakfast; as of the time of this writing, renovation is waiting on an environmental impact report concerning the local population of monarch butterflies and the nearby Soquel Creek.

The mansion is built in a vaguely Spanish style, with tile roofs, a barrel-vaulted patio, and a massive column of bay windows facing Soquel Creek. It is now in very poor condition; most of the interior has rotted out or been destroyed by vandalism, none of the windows remain, and about half of the roof tiles are broken. The concrete exterior walls are intact, but are covered with graffiti of widely varying literacy and artistic merit. It is very heavily boarded up; all doors have been replaced by padlocked and alarmed steel barriers, and all easily accessible windows have been covered by thick plywood sheets. The grounds are largely overrun with ivy and poison oak. Gaining entry is difficult without power tools or a crowbar, but it's certainly possible with enough determination and/or stupidity.

At least four ghosts have been reported in the mansion (a woman in a Victorian-styled black dress, a man with glasses in the empty fireplace, an injured man calling for help from the basement, and an angry dog), as well as cold spots. While the accuracy of many of these reports is questionable even to believers in the supernatural, the house's empty windows, ruined interior and generally ominous appearance are certainly enough to stir the imagination. At least two corpses have been found nearby, doing nothing to dispel the rumors of haunting; one man was injured while falling through damaged floors and apparently died of thirst, while the other died of unknown causes on the mansion's grounds. Rumors also persist of secret passages within the mansion, possibly dating from the Prohibition era; the most consistent of these usually mention tunnels running from the house's basement to the nearby creek.

Sources:
personal experience
links in http://alumni.cse.ucsc.edu/~neal/rispin
http://www.capitolamuseum.org/1930rispin.html
the rest of a Google search