Octagon House: the eight-sided 1861 Cow Hollow museum has two open days left this year

At the corner of Gough and Union streets in Cow Hollow, an eight-sided wooden house sits behind a garden. It looks like a curiosity, and it is one. The McElroy Octagon House, built in 1861, is one of only three octagon houses left in San Francisco. The others are the Feusier Octagon House on Russian Hill and the Marine Exchange Lookout Station at Lands End.

When you can visit

The museum and garden at 2645 Gough St. are open from noon to 3 p.m. on the second and fourth Sundays from February through November. That leaves two open days this year, Nov. 8 and Nov. 22, before the house closes for the winter.

A Gold Rush house

William C. McElroy, a wood miller, and his wife Harriet Shober bought a lot across the street in 1859 and built the house between 1860 and 1861. It originally had two floors, four rooms on each, and a winding staircase in the middle. The family lived there until around the 1880s, when it became a rental. One tenant was Daniel O'Connell, a co-founder of the Bohemian Club. The house was badly damaged in the 1906 earthquake and changed hands many times after that.

Saved and moved

By the early 1950s the house was vacant and neglected. The National Society of The Colonial Dames of America in California, which says it saved the house from destruction in 1952, moved it across the street and restored it. The restoration was led by Warren C. Perry, UC Berkeley's former dean of architecture, and changed the original floor plan to work better as an event space. The house opened as a museum by 1953. Condominiums now stand on its original site.

The Colonial Dames run it as a museum of decorative arts from the Colonial and Federal periods. The organization says that when it rescued the house, almost nothing was known about its early history, and its account of that history ran in The Argonaut, the journal of the San Francisco Museum and Historical Society, for the house's 150th anniversary in 2011. San Francisco made the house a city landmark in 1969, and it joined the National Register of Historic Places in 1972.